Why did old phone numbers start with letters? (2015) | Hacker News Reader

Why did old phone numbers start with letters? (2015)

mentalfloss.com

87 pointsthunderbong142 comments

The article seems to imply that in the US the names were arbitrary and just served as mnemonics?

In France it worked in the same way, but the names referred to actual places: either the name of the town when it was small enough, or a district / neighborhood for larger cities.

So your number would be "Trocadéro-12-45" or "Lourmel-78-98" for instance; and, starting in 1928, you could dial it in directly on your phone without speaking to an operator, by using the first three letters of the indicatif (TRO or LOU in those cases).

This system was replaced in 1963, but the new numbers simply reused the numbers that were represented by the names. Because of this, many people still told and wrote their numbers using the old names (that still worked), well into the 70s. I'm old enough to remember people telling me their numbers using the indicatif.

More information (in French): https://fr.wikipedia.org/wiki/Anciens_indicatifs_t%C3%A9l%C3...

Edit: Another fun fact: numbers followed the order they were attributed, so if your number was Tours-00-01 it meant you were the first one to have a phone number in that town.

This being France, getting the telephone was a complex bureaucratic affair and many times you had to prove you really needed one, because they were in short supply.

My grandmother was extremely proud that her father had a very low number (some time in the 1920s probably?) because he was captain of the firefighters and needed to be reachable at all times. It was a story she told often.

> “My grandmother was extremely proud that her father had a very low number”

In Finland, a local operator built the world’s first commercial GSM network back in 1991. They initially sold four-digit phone numbers as a perk. (Combined with the country code and the operator code, the numbers today look like this: +358 50 1234)

Those short numbers are still being resold by their owners. I’ve heard some of them go for tens of thousands of euros.

The psychology of valuable numbers is pretty interesting. NFTs are basically that. You don’t even own the JPEG, you just own a number in a database that indicates that image. And if your ugly ape picture number is 24 and some poor sap has ugly ape picture number 1581, surely that makes you richer and more envied.

We're not immune to this. Internet points or "karma" on this very website work the same way.

Absolutely. But the coveted big number, an ever-accumulating ledger balance, is a different kind of valuable number than the small number, which generally represents a distance to the origin of the number cult. Lower is better because it’s closer to the source.

Elon Musk has the biggest big numbers of them all. But that doesn’t mean he could acquire every kind of valuable small number that exists. He can definitely buy a low-numbered NFT, and he can probably buy an early Picasso (though there aren’t many not in museums). But he can’t buy himself a low Erdős number for example.

This is what traditionally separates the nouveaux riches from old money: the first are interested in the big numbers, the latter in the small ones. (“My great great grandfather was the second Earl of Somethingdom.”)

> But he can’t buy himself a low Erdős number for example.

Why not? With that much money I'm sure he can spend enough to convince somebody with a low number to "collaborate" with him in some capacity. Even if it's spell checking the English text or something.

It's true, academic institutions are quite good at selling their prestige to donors (honorary titles, etc.)

So probably he could do this most easily by donating a pile of money to an institution who employs someone with a suitably low number, who then paper-collaborates with the rich donor.

Nobody loses face in such a coordinated sell-out. The mathematician did it because it got the math department a $100 million grant. The rich guy is now a recognized patron of the noble science. The university administrators are pleased that they can direct their fundraising efforts elsewhere.

And eventually the rich guy's son gets to use this as a talking point to highlight how he's probably inherited some of the family genius: "My father was actually quite an accomplished mathematician too" — nobody remembers or cares 30 years later how it actually went down.

> nobody remembers or cares 30 years later how it actually went down

Or, nobody remembers why the number is valuable. That was the problem with my grandmother; when she told the story to us, telephone numbers had looong ceased to be significant (or indeed, hard to get) so the fact that yours was small or big didn't mean anything, and it sounded so strange to us that one would cherish it.

Musk managed to buy the low low "number" of co-founder [0] of Tesla. So in my opinion if something is arbitrary it can be bought with enough money.

[0] https://www.cnet.com/culture/tesla-motors-founders-now-there...

https://www.sciencenews.org/article/theorems-sale

A very similar thing happened with ICQ numbers where short (or pretty) numbers were prestigious and were sometimes sold.

I think there's a difference from NFTs in the fact that ICQs and telephones were heavily used tools for communication, this is what lends these numbers the prestige. Since everybody used them to communicate with you, everyone saw that prestigious number.

In comparison, NFTs aren't really attached to something of value in the same way and are not interesting/prestigious to anybody outside of people interested in those NFTs specifically.

We had a phone number with 6 digits (without the international code in front).

When my father had to enter the phone number in some hotel form when he was abroad the guy was totally convinced he must be some sort of royal, president or another kind of very important person, when in fact we are just from a very rual part of a very small nation.

> The article seems to imply that in the US the names were arbitrary and just served as mnemonics?

> In France it worked in the same way, but the names referred to actual places: either the name of the town when it was small enough, or a district / neighborhood for larger cities.

Named exchanges are before my time, but my understanding is that the names were kind of sort of arbitrary; they'd try to assign the exchanges meaningful names, but that's not always possible, especially when trying to also balance other numbering priorities. In the 1950s, AT&T put together a list of recommended names for exchanges, you can see on wikipedia [1],

[1] https://en.wikipedia.org/wiki/Telephone_exchange_names#Stand...

"Murray Hill" is a neighborhood in manhattan as mentioned in the article, I found a source with some more examples [0]:

"For example, in a 1932 Manhattan phone directory, you can see the numbers listed by exchange. CH-elsea. ST-uyvesant. This was before direct dial, so there was no need to figure out what CH or ST converted to as numbers on your rotary dial; you’d simply ask the operator to connect you. Once people dialed directly, the first two letters became the first two numbers of the exchange. In that 1932 phone book, the number for the store Bergdorf Goodman, located near the Plaza Hotel, is given as Plaza 3-7300. That translates to 753-7300, which is still the store’s phone number today."

[0] https://www.washingtonpost.com/news/politics/wp/2017/04/07/a...

Oh ok, so it seems it was the same. I re-read the article and still find it unclear on this point, but your comment is much more explicit. Thanks!

Great explaination, I'm just a bit disappointed you didn't use "Asnières-22" in your examples :)

> My grandmother was extremely proud that her father had a very low number

So, Slashdot cred is not a new thing :-)

I grew up in the Seattle area in the mid-1950s and 1960s. One of the exchanges in Seattle was MUtual, starting with MU just like NYC's Murray Hill. One year Shari Lewis, the puppeteer famous for creating the Lamb Chop and Charley Horse characters, came to Seattle to host a telethon, probably for what is now Children's Hospital. She kept forgetting that MU was the prefix for Mutual and told us to dial Murray Hill instead, before catching and correcting herself almost every time.

When they started using numeric dialing, they simply substituted two digits for the letters. My exchange was VErnon, so the two digits became 83. It was confusing for long time as I lived over the county line from Tacoma, which also had the same prefix but was long distance and remained so until cell phones pretty much erased the local long distance regime.

Grew up on the Eastside (of Seattle) in the SHorewood exchange. Learned our number as starting with "SH".

It was kind of fun when the first two digits of a number gave you a pretty decent idea of where someone was.

One other fun fact about numbering, the most frequently dialed exchanges, those for big cities would use the lowest numbers, e.g. downtown would be 223 for the exchange and big cities area codes 212 and so on. The reason was not for the convenience of the dialer, remember it was rotary dial way back when a lot of those first got assigned, it was because the signaling was in band so the longer it took for the dialing to happen the longer the trunk was seized. If you have ever used a rotary phone, you'll notice it takes forever to dial 909 for example. So to optimize for the network they made the most frequently used numbers, most populated places, have the lower digits.

That also explains why European emergency numbers are often 11X, including 112 which is the universal emergency number in the EU and the GSM standard (so it will work on your mobile phone too).

It doesn't explain Britain using 999 or Australia using 000.

Maybe the thinking was that you can easily slip with your finger or mindlessly dial something, then accidentally dialing a 1 or 2 is much more likely than doing the same with 9 or 0 which needs ten times the pulses (and the time) needed for a 1. Having grown up with rotary phones, that would make sense to me.

The UK originally considered using 111, but there were problems in that on windy days, trees etc brushing the lines could generate momentary disconnections = a pulse = digit 1. So false calls.

999 was choosen because it was easy to find the number 9 on the dial in the dark.

On a rotary dial 9 is hard to find, 0 or 1 would be much easier. Was the UK early with button dials?

It's not that difficult -- you find the metal fingerstop, and then move two around from it (0 and then 9). 000 would be easier, but it seems like that was already taken for other purposes.

I believe this was a plot point in one of the original stories about Paddington bear. Something about his fat finger.

000 makes lot of sense to me. It is the last digit available, so it can be quickly dialled.

Whether 0 comes before 1 or after 9 has been the matter of some debate!

But by the time typewriters started cementing the order of things, 0 came last, and on all the rotary phones I see on google images, 0 would take the longest to dial.

Do rotary phones in Australia flow backwards? xP

> Do rotary phones in Australia flow backwards? xP

They rotate the same direction as water circles when you flush a toilet.

They do in NZ: https://en.wikipedia.org/wiki/Rotary_dial#/media/File:New_Ze...

This wasn't a problem until direct international dialing became a thing, and then all of a sudden pulse converters had to be installed.

The emergency number there is 111.

With pulse dialing "1" is one click, "3" is 3 clicks, "9" is 9 clicks

You can't have zero clicks, so "0" would have to be 10 clicks

Yes, dialing 0 sends 10 pulses.

In which case it needs to be after 9

Sorry for the offtopicness but can you please email hn@ycombinator.com? I want to send you a repost invite.

This is not universal. E.g in Sweden we used one pulse for 0, two for 1, etc

My understanding of 999 was in order to stop accidental signalling of the intent to dial the emergency number by way of noise on the line being intepreted as dial click, which this article on BBC news seems to corroborate [1].

Having said that, that doesn't really then line up with 112 for mainland European countries, unless that is a relatively modern occurrence and they historically had different emergency numbers?

[1] http://news.bbc.co.uk/local/london/hi/people_and_places/hist...

112 didn't really start getting widespread support until after pulse dialing had mostly faded away.

Indeed, 999 is rather old, and many other European countries had different short codes such as 15, 17 or 110 and often they were different for police, ambulance and fire fighters, and some countries had no central emergency number at all. The coordination on 112 as a common Europe-wide number (including the UK) happened somewhere in the 1990s. Pulse dialing was on its way out by then, although it is the reason why it ends in a 2 and not a 1.

Here in Croatia they still have different numbers available for the different services, alongside the 112 "catch all".

112 – general emergency line

192 – police

193 – firefighters

194 – emergency medical assistance

195 – search and rescue at sea

There is also this:

1987 – road assistance

Emergency numbers would rarely go onto trunk lines though, so in that case, I suppose speed of dialing was actually the main concern.

A reminder that both direct-dial long-distance <https://yewtu.be/watch?v=C7YM9Sz9wxo> (1936) and direct-dial calling <https://yewtu.be/watch?v=uaQm30DDHL8> (1951) were once novel technologies which needed to be introduced and taught to the public.

Was television in many homes in 1936? Or even 1951? How were these messages broadcast?

For matter of comparison, my country did not get its first television broadcasting station until 1967.

I can only go by Back to the Future, in 1955 marty's middle class ancestors are proud of their color TV, and scoff when marty says he's got 2 of em, "Nobody has two television sets."

1936 would have been the earliest TV broadcasts ever - the Berlin Olympics ! According to wiki the only viewers would have been in locations set up around the city just for the event.

So now I am quite keen to find out what context these videos were meant to be watched

EDIT: oh, it's in OPs link: "This short subject newsreel was shown in movie theaters the week before a town's or region's telephone exchange was to be converted to dial service. "

I suppose in cinemas. Before the feature. Like the news at the time with the Newsreel: https://en.wikipedia.org/wiki/Newsreel

As others have noted, the first of these videos was distributed as a newsreel, playing before feature films in towns as AT&T rolled out direct-dial.

I don't know how the second was distributed, though Wikipedia suggests newsreels continued in mainstream until the late 1960s, which would suggest that the 1951 video also saw newsreel distribution as a primary mechanism.

<https://en.wikipedia.org/wiki/Newsreel>

They even had this in the Simpsons in the 90s, so not even 50s era!

Mr Plow gives his phone number as Klondike 5 3226 and the jingle says "KL5 3226"

Pretty sure Seinfeld gave a KL5 number once too.

Yea, Seinfeld phone numbers were all over the place. Letters in the numbers, 5 digits numbers and then towards the end the standard 7 digit and 10 digit. I didn’t watch it contemporaneously, but rather pretty recently and I kept thinking, there’s no way the show is that old that they were still using letters in phone numbers in NYC.

I was a kid when Seinfeld aired originally and didn't find it that weird. My grandmother would often give her phone number to older people as SHerman-2xxxx. She stopped doing that after Chicago and the suburbs split 312 and the suburbs became 708 in ~1990. I can see it still being common among older people in the 90s in Manhattan until more area codes were added towards the end of the decade (there was also some restriction of the 212 area that factored into a Seinfeld episode too).

It's worth noting that during the run of Seinfeld the number of telephone numbers was growing rapidly. Until dial-up internet took off it was pretty uncommon for a house to have 2 numbers - usually just well off people or those who ran businesses out of their homes. Then dial-up internet happened and phone rates were also getting cheaper, so a lot of families opted for a second line in their home to not tie up the primary phone for hours on end. At the same time beepers, then cell phones went from something for doctors (and other important people) and drug dealers to "pretty common", adding to the growth rate of assigned telephone numbers.

Put another way - during the run of Seinfeld my grandmother lived in the same house and had the same 7digit phone number that she had since the 1940s, but got 2 new area codes (708 split into 847, 630 and 708 in ~1995), and 10 digit dialing was required not long after. All the rapid (compared to decades of sameness prior) change is what finally broke the old habits, more than silly things like touch tone dialing or direct dial long distance.

I liked this video I recent watched, which covered the history of this, centered on Seinfeld: https://www.youtube.com/watch?v=viLVO46FQX0

To summarize that well padded video, New York switched to digit dialing in the early 70s, but some New Yorkers considered their phone numbers to be a status symbol because the phone number identified which neighborhood you lived in. Some kept using them up until the 80s. Seinfeld is set in the 90s, but is based on the time Larry David and Jerry Seinfeld lived in the city a decade earlier. So the show contains anachronisms like Elaine giving out her phone number in a format that had finished dying out years before the show was set.

Good video, thanks!

Yeah, during the period you mention, a lot of old urban area codes were being split up with what would have used to have been streetcar suburbs (and sometimes still literally sort of were around Boston for example) getting a new suburban area code. The result is that some number of people who had always identified as living "in the city" now found themselves with a suburban area code. (And, yes, real people actually did care.)

As you say, I recall there was some Seinfeld episode where someone broke up with someone because they didn't have a 212 area code or something along those lines. Which wasn't a totally outlandish plot point.

Twice. I hate that I know this.

Klondike5 had caught me by surprise so I looked into it. Also Jerry's phone number changes in between the two episodes.

Came here to post this haha. Great minds, etc.

https://www.youtube.com/watch?v=QacpBRPonzM&ab_channel=Thing...

I'm old enough to remember my home phone number beginning NIagara-8 when I was a latch-key kid in !970's Kansas City.

We were VIking-2 in Lawrence until around that same time.

Olathe had POpular 4 and STate 2

We had "RH" - but it's not in the AT&T list that the article points to, and it has no obvious georeferent. RHode island was the wrong state, RHodesia was suboptimal, and RHombus was non-geographical and too esoteric. RHinovirus perhaps.

"RH" is surprising - you'd want words that people would spell correctly, and PI/RI/SI/PH/SH seem easier to work with if you're trying to get 74.

Mr Burns answers the phone "Ahoy-hoy" because Alexander Graham Bell proposed that as the greeting for answering.

No fucking way! Wow.

The fictional KLondike exchange was often used back in the day for movie/TV phone numbers. And a look at a phone keypad shows that we would now say 555-3226...hey wait! That's exactly how we would give a fictional phone number today! (Technically, only 555-0000 thru 555-0199 are reserved for this purpose, but not every fictional number follows that rule.)

San Francisco had a Klondike exchange (and apparently Columbus, OH did as well according to wiki).

That name again is...sorry.

This article, and Wikipedia, and apparently everyone else, all cite the same 2001 nytimes article regarding the Committee of Ten Million to Oppose All-Number Calling. How influential were they, really, if that is the only remnant of their existence?

Here’s a New Yorker piece from 1962 mentioning them, at least:

https://www.newyorker.com/magazine/1962/10/27/comment-4830

I don't remember the exact timeframe but it wasn't far from then when I switched from Verizon to Comcast and it meant I had to switch phone numbers for exchange reasons. It was sort of annoying and, among other things led to me getting very persistent calls from some debt collector for a while.

My cell phone number now is one I've had for ages and actually dates to when it mattered what area code you had for cell for cost reasons based on who you called before "favored" area codes became scarce. Think there was a Seinfeld episode based on that too.

Haha, their big plan was to make up new prefix names.

The prefix names they offered are key to the joke:

>The group offers a handy guide to the construction of entirely personal arrangements, such as HAberdasher, YLang-yland, KNife, and WRappingpaper.

One more remnant is the parody protest song from 1963 that I linked at top level here.

If you are interested in this kind of stuff, check out C*NET aka CKTS or Phreaknet. Or maybe the Connections Museum on YouTube. There are a surprising number of people doing weird stuff with old electromechanical switches or emulations thereof.

https://ckts.info/

https://portal.phreaknet.org/

https://www.youtube.com/@ConnectionsMuseum

People are mentioning this was on the Simpsons, but I remember my mom telling me this was how they used to name phone numbers when she was a kid and she wasn't even born until 1961. Lester Freeman in The Wire from 2003ish was still calling the prefix of a phone number the "exchange," even when talking about cellular service.

Born in 1961 and these articles don't touch on one thing that I remember when I was a kid: you only needed 5 numbers to dial if you were calling someone else in the same thing. This was the case at my grandparents in Bay City, Michigan in the late 1960s. My cousin's number was LIncoln 2-9729

I have never understood how that worked despite my father working for the phone company. Dad explained a lot of things, but that wasn't one of them.

There was a timeout. If you had touch tone it was faster to dial the whole thing because then the call would connect straight away.

Worth it on rotary phones though. Those were so slow to dial, especially if someone had a lot of high digits in their number.

We didn't have tone dialing until after we had the internet because my dad was cheap and didn't want to pay the fee for tone dialing (vs pulse)

Interesting.

In the European countries in familiar with, there would be a prefix digit (usually 0) to show a call was not local. (And a different prefix to make an international call, usually 00.)

So if you live in London and have a landline phone, you can call Westminster Council by dialing 7641 6000. Outside London you'd need to dial 020 7641 6000.

The 0 isn't really part of the number, so from abroad you typically dial 0044 20 7641 6000 (but the international prefix varies, so it's written +44 20 7641 6000.)

Alternatively, in some places they actually made sure there were no common prefixes.

I'm from the UK, but IIRC I think the US phone numbers originally used the 2nd digit to discriminate whether the first 3 digits were a local (7 digits) or national (10 digits).

Not sure where your 5 digit example fits into that though, that'd suggest there was actually 3 levels of discriminators originally. It's certainly plausible when there were relatively few numbers used, with the push to 7 and 10 digits only when the number space was getting fuller so that those prefixes could be reused.

From 1963: the all digit dialing protest song, "Let's All Call Up AT & T and Protest to the President March" by Allan Sherman. Lyrics:

https://mojim.com/usy129446x2x37.htm

Audio:

https://www.youtube.com/watch?v=hCFLanFgUPI (and many others)

Allan Sherman also wrote Hello Muddah, Hello Faddah https://www.youtube.com/watch?v=er50h8W8vWg

I could be wrong but I think there was a period after the exchanges were used (no need to use full names) and folks continued using 2 letters as a prefix to a number because they were easier to remember that way (can still remember my cousin's 70s number to this day PL78750). You would look at the phone to determine the number for P and L.

I still remember a scene from Seinfeld where George is at the unemployment office and when the lady asks him for the business's phone number, he says KL5 8383.

An alias of the 555 fictitious exchange prefix, also sometimes KLamath 5 or KLondike 5:

<https://en.wikipedia.org/wiki/555_(telephone_number)>

It's so annoying that they only used one example (Murray Hill) which is actually MU and not MH, which required me to re-skim it a few times to grok what was going on.

It would have been nice for the article to provide several examples of the mnemonic.

While I've been aware for quite a few years that the telephone system used to use names for exchanges (eg, Pennsylvania 6-500), it took a few MORE years for me to realize that it mapped to PE6500, or 736500. It's one of those things where, if you understand the system (like my parents did), it's obvious and it doesn't occur to you that you might have to explain the letter-to-number mapping .

Fun fact: you can still call Pennsylvania 6-5000 and get the hotel which has closed in the last few years. They used to play The Glenn Miller song when you called them...

Maybe not anymore. The building is being demolished. https://www.archpaper.com/2023/08/last-remnants-hotel-pennsy...

New owner claims he's going to keep the old number.

https://en.m.wikipedia.org/wiki/PEnnsylvania_6-5000

I called it before I wrote the comment. A few years ago I got the song, just before I wrote my comment I got a recording saying they were closed permanently

The article linked to the full Ma Bell list: https://web.archive.org/web/20150317062651/http://www.ourweb...

It's strange to me that there are 5-6 options for each exchange, instead of a canonical name.

The article did a really poor job of explaining the logic.

> It's strange to me that there are 5-6 options for each exchange, instead of a canonical name.

The point isn't to assign them canonical names, but to define a mapping from the two letters at the start of a word to two-digit codes. These letter-pairs are chosen so that meaningful words can be formed with them (that's why there is no QX, because no English word starts with QX) and that they are distinguishable (which is why there is a BA but not BE, BO, or BU: it would be hard to distinguish BAldwin from BEldwing, BOldwin or BUldwin).

There isn't a single canonical name because the purpose of the code is to allow cities to define their own area codes with memorable names that vary based on the location. One city might use UNiversity (86), MUseum (68) and CEnter (23).

But using UNiversity or MUseum wouldn't make sense in a different city that doesn't have a local university or a particularly notable museum. But they can still use the same area codes with the mnemonics TOwn Square instead of UNiversity (86), OVerlook instead of MUseum (68), or CEdar Avenue instead of CEnter (23).

> (which is why there is a BA but not BE, BO, or BU: it would be hard to distinguish BAldwin from BEldwing, BOldwin or BUldwin).

But there is a BU, as immortalized in the Oscar-winning Elizabeth Taylor film "Butterfield 8"

My childhood phone number in Brooklyn was a BU (28) number, though even when I was a child (1970s) the use of letter exchanges was basically a holdover of a more or less dead practice. (But the use of letter exchanges in phone numbers persisted for decades after that in New York City in store signs - I think there are still some in use today.) In Brooklyn, BU stood for "BUckminster". I had this idea that this was connected to there being a "Buckingham Road" and a "Westminster Road" in the area I grew up in (Ditmas Park West and environs) but I'm not sure if that was something I or someone I knew made up. I'm sure it had nothing to do with Buckminster Fuller.

Ah, I had forgotten that exchanges are local so the exchange number is not nationally unique.

Well that's one mystery solved:

https://youtu.be/QacpBRPonzM?si=7kFqTOe9S9F0OORy

I never knew why Homer gave the fictional number 'KL5-3226' ("Klondike-five") for his Mr. Plow commercial.

I knew the guy who had 1-800-FUCK-YOU, and he used it to sell those classic bumper stickers: "How's my driving? Call 1-800-FUCK-YOU!"

So he could have literally earned “FU money”!

"had"? What happened to it?

My mother explained this to me (in the '70s or '80s) when I was complaining about them changing or phone number... they took the first three digits of our seven digit number for something. Her number used to be "Tuxedo" (TX) something, something, something.

I don't know if she joined the "Anti-Digit Dialing League" that the article mentions, but I could tell she liked she old number.

Her point was that they'd changed the system before and surely keep changing the system (indeed, some years later they changed our area code).

I wonder what the next change will be?

EDIT: searched... Tuxedo was actually TUxedo, or 88. Also: nemonics can really work. It's weird I can remember the first two digits of a phone number I head about once, that had stopped existing before I was born.

Before more advanced computerized call routing and SS7 signaling changes area codes had to map to one specific non-overlapping region. So when a metro area needed more exchange prefixes they had to split the area code and some subset of customers got pushed onto a new area code.

In more modern times they assign an "overlay": multiple area codes can be assigned to the same region so there is no need for splits.

Actually the system isn't really hierarchical anymore. Thanks to number portability optimizations any switch can lookup the destination switch for a 10 digit number. Thanks to faster computers and larger storage that isn't the problem it once was.

There's plans for eventual expansion, [1], although I wouldn't bet on any of the current plans to be the one that's eventually chosen. Current growth levels seem to give us capacity until beyond 2050. [2]

Number expansion does regularly happen around the world; it's not fun, but it's part of life.

[1] https://en.wikipedia.org/wiki/North_American_Numbering_Plan_...

[2] https://www.nationalnanpa.com/reports/October_2020_NANP_Exha...

We'll all be on IPv6 by then!

The exchange prefix once mapped to a single physical central office location. It wasn't until the 1980s that there was much lookup involved in local calls. In telephony, converting phone numbers to routes is called "translation". Before cheap memory, translation was really hard. In "A History of Engineering & Science in the Bell System: Electronics Technology", there are descriptions of various special purpose devices developed to store data. Hand-wired ROMs the size of racks. Optical metal card readers for long distance route storage. By the 1980s, little 3B minicomputers running a real-time variant of UNIX.

It was a long time before numbers were just 10 digits with arbitrary mapping.

Anyone interested in the pre-digital switching can spend some very satisfying time at the Connections Museum.

https://m.youtube.com/watch?v=Gsx2ZsYggGw&t=956s&pp=ygUSY29u...

The all mechanical switches are flat out amazing, and quite performant, given the tech. Often, it was less than a second from off hook to dial tone! The video I linked has some great detail.

And they did not have amplifiers! One implication was surprising! Say you made a machine to generate dialtone. Great. It could service X number of subscribers based on its capability and Ohm's law.

Want or need more? Get more or bigger machines. It is crazy!

Another implication was each circuit needed to be ideal in order to carry voice. No amps meant a closed DC loop with the mic able to modulate voice via resistance. This is part of why the telcos resisted any attempt to connect to their network. It was easy to load it all down which required a service call

Anyhow, I was quite surprised to learn how telephony worked and have appreciation and respect for the engineers and their work connecting the nation.

I vaguely recall there was a Twilight Zone episode that might have used “Klondike” - anybody happen to know which one? I think they picked up the phone, the operator was either already on the line, or they might’ve dialed zero, then requested the number they wanted to call. I just remember it wasn’t completely numeric.

I always had wondered what was going on with that phone number, and I think these comments have pretty much solved the larger mystery, now I’d just like to re-watch that scene again with this new (to me) context.

Klondike 5 - ... Would mean a 555 number which is the example.com of exchange numbers.

I don't recall if they actually used "Klondike", but I'm gathering as much based on the other comments.

I used to live in a small beach-side community in New Zealand, this was back in the time of mechanical (stepper) telephone exchanges. Locally we had 3 digit phone numbers - dialing a "2" would get us a circuit (a actual physical pair of wires) to the nearest city, in the city dialing "22" would get you a circuit to our community.

There were asmall limited number of wires going over the hill to town, if you dialed "222222222222222222222222222222" ......

There's good documentation on the UK version of this on wikipedia: https://en.wikipedia.org/wiki/History_of_telephone_numbers_i...

Two letters and a number formed the basis for UK numbers within the bigger cities, and later 0 + two letters + number for national dialing codes when they were introduced later.

So, the big cities (when I was a kid, these were 01 London, 021 Birmingham, 031 Edinburgh, 041 Glasgow, 051 Liverpool, 061 Manchester, so again using the letters) had the local part with local exchange 2 letters + number and a 4 digit number within that local exchange.

Smaller towns and cities had the longer codes (0ABx), again using letters - e.g. the old Coventry code was 0CO3, Bolton 0BO4 etc, and 5 (and later 6) digits for the local part.

At one point when I was still quite young, I lived in a very small village with phone number 205, and the public phone box was 200 - I think the numbers got as high as 230! In addition to the full STD codes, the neighbouring phone exchanges had 1 or 2 digit prefixes so you could call them almost like local numbers. Our village was similar, from the main town you used a 2 digit prefix, and our STD code was the main town's STD code plus that prefix. My dad told me that before the national STD codes were introduced, if you wanted to call another town you either had to call the operator and ask them to connect you, or you had to chain all these access codes together to jump from exchange to exchange until you got where you wanted. Apparently that still worked when he told me, but I was too young to know anyone further than the next town, so I never tested it!

When I was 9, I lived in a suburb of Liverpool called Gateacre (pronounced "Gatticca"). I can still remember our phone "number": GAT1965.

I love to figure out words from my phone numbers, and I've had some doozies over the years.

Of course, there are apps and websites to calculate those instantly now, and you usually get the opportunity to choose a number at least from a menu, so finding a pithy word or phrase is elementary, my dear Watson.

And this is likely why you'll sometimes see reserved "555" numbers in tv shows represented as "KL5". e.g. Mr Plow: https://imgur.com/a/XIRKn6W

Also frequently called "Klondike 5"

I own and have wired-in a number of 1930s and 1940s telephones (pulse dial still works in the UK). They are little more than ornaments now but they work.

One of them contains a mini 1960s hyper-local directory of exchanges (names and numbers) on a pull-out tray. You would lookup the exchange name, dial that, followed by the handful of digits required to reach the subscriber.

When I was a kid in the 80's (and probably early 90's) I remember visiting my grandparents and other family in Frederick, Oklahoma, and everyone there had 5-digit phone numbers. I still remember my Aunt's #, because we would stay with my grandmother for weeks at a time in the summer and would often call over to my cousin's house.

In my country, you did not have to use area codes when dialing a local phone number. I guess you had the same experience

Similar: I was a kid in S. VT in the 60s/70s and everyone using the phone system used five-digit dialing. You were assigned a 254-xxxx or 257-xxxx number, but when dialing you only had to use the last five #s, as the "25" prefix was implicit. I think there was a bias on the part of the phone company for assigning 254- prefixes to residences and 257- ones to businesses, but I'm not sure how strict they were about it. I can't recall if using the full seven digits worked when calling within those two prefixes, but I think that it did. I don't remember anyone ever using alphabetic prefixes, which makes me wonder if they were perhaps used there before I was born or if it was a convention only in big cities (my town was ~10K, a bit under).

One of the first numbers I remember is my father's auto service station: LA3-7840

This was in the 70s!

using my landline, i generally just give people my last 6 digits - one of the reasons i like using landlines for local calls, actually

Most major metro areas in the US no longer support seven digit dialing.

And I love how they call it "10-digit calling" even though it generally requires 11 digits (or 11 button presses on cell).

Huh? You don’t if it’s a “local” call. Probably more of a US thing where mobile phone long-distance charges went the way of the dodo a long time ago. But they’re still very much a thing in Canada and just starting to die off.

I'm not sure I follow. Obviously cell phones and cordless phones have a talk button, but that's not very digitlike. When I operate a landline, I just enter ten digits: 9095551212. Are you implying a leading 1 would be necessary? IME, it isn't for local 'ten digit dialing'.

The 909 area code? What, are you buying meth?

411 on the 909: https://www.dictionary.com/e/slang/909/

And even more if you count the taps/swipes to unlock the screen! So people generally don't.

Sometimes it’s just implied. At the pizza place where our cabin is (ok, it’s like a 25 minutes drive), you can just give them your last 4 numbers and they assume the rest.

Up until the 1980s my great-grandparents lived in the town where they only used four digits for all local calls. It was pretty nice, they tell me

> Sometimes it’s just implied.

Like in Nova Scotia/PEI. Technically there are two area codes, but no one actually knows what the second one is.

The other one is undesirable because if people see it they often won't even answer, assuming it's scam or such. That's how unknown it still is

902 was introduced in 1947, making it one of the first area codes used in Canada and it's been completely ingrained in the region since then. The second was only introduced in 2014.

That’s interesting.

In the US spam calling is so prolific I assume anyone using my area code is a spammer spoofing. Though it helps that I don’t live where I got the phone number anymore.

You must live in a very remote area to still support that. Not to mention to still have a landline, no one I know in my area will even give out a POTS line, you can only get VOIP and most households don’t have that anymore either, aside from the outrageous cost all the providers charge for a single line, there’s so many taxes and fees you end up paying close to 100% more. (E.g $40/m for the line ends up being $80).

Most families that have young kids who are old enough to place calls but not have a cellphone appear to just some form of internet VOIP like ooma.

Even living someplace that has fairly poor cell reception if WiFi assist isn't working for some reason, it's really hard to justify a landline as "backup" for the rare occasions I wished I had it. I got rid of it a few years ago and, while there has been a day or two I wish I had it, hard to make the case.

(And, yeah, if you're going to be VOIP anyway, if your internet and/or power is hosed you're probably not in a better place anyway.)

Wouldn't it be nice if your cellular provider had a SIP gateway for your number as well, and if it rang your phone it would also route to your SIP device?

Like, it's already routing calls through the WiFi. Is it really that much harder for them to allow two devices to register for the number and connect the first to answer?

My German mobile phone provider supports that! It's really handy when traveling internationally; I usually receive my calls over SIP without incurring any roaming charges (due to using a local SIM).

In the US, Google Voice allows a conceptually similar thing (but you need to give everybody your Google Voice number or port your "real" number there; then you can forward calls to both a mobile and a SIP number, with both ringing for incoming calls).

Parent might be British - POTS is still widely available here, although not terribly popular. It's about as expensive to get a POTS line as three unlimited-calls 4G SIM cards, unless you combine calls with your broadband and can save money on the line rental.

i use voip - it is cheap, sky, uk.

There is very little reason not to use VOIP - a friend of mine, a former telephone engineer and entrepreneur, even has his calls set up to be automatically routed to his mobile phone when he is out.

Isn't POTS being shut down in the UK in 2 years from now? https://www.ebcgroup.co.uk/news-insights/all-of-your-questio...

Yikes, thanks for the warning. It's a great idea on a technical basis, but I really hope they don't make this an excuse to get rid of the last telephone boxes (which after this change should be free for local calls anyway, considering how cheap VoIP is).

nope, i live in lincoln the major city in lincolnshire

I recently came across a sidewalk stamp with a 4-digit phone number which was quite interesting to see.

Without RTFA I'd guess for operators to punch them in while connecting your call.

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