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Comment by nezumi | Hacker News Reader

But that world does still exist: I often find myself ssh'd into a desktop tmux session, via my laptop tethered to my phone's internet connection. In that situation, I am highly appreciative of vi's 300 baud history.

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In 1979 I needed a terminal, so I wired-in a UART to my homebrew Z-80 system and hooked it up to a Cat acoustic (300 baud) modem.

I wanted to use Emacs on my guest account on the MIT PDP-10s to do my editing of school projects, so I could FTP and compile them on NBS-10's Pascal compiler, print out the results in the machine room at NBS, drive 20 miles, and hand in the work.

Rather than use punchcards. /Now/ you understand. Anything but that.

To make Emacs usable at 300 baud, I wrote a SUPDUP terminal emulator. SUPDUP was an abstract terminal type that MIT Emacs understood internally. It sported character and line insert/delete, and region scrolling, and it made the screen update tolerable.

It's hard to convey the electric sense of an editor that self-inserted characters. The productivity boost was amazing. It was worth all the effort, and I'm sure I was having a lot more fun than the other poor sots at the U who were having to line up for keypunch machines and deal with two-hour job turnarounds.

Also there is zile, a 130Kb emacs clone. http://damnsmalllinux.org/cgi-bin/forums/ikonboard.cgi?act=S...

There are a number of small Emacs clones (I wrote one for the 6502-based Atari 800 back in the day). They are certainly better than nothing. None of them existed until the mid 80s.

Ironically, 130K is tiny todya, but more than half the address space of a PDP-10 :-)

Yes, bandwidth is always better, but latency spikes are real, even when sitting in your office you can get routing issues or congestion or who knows what making things very frustrating for anything that needs rapid visual feedback.

HN is also an interesting community because of the fact that we all have relatively fast connections. Bungie (guys who made Halo) found out that if you want to be accessible to 99% of connections you need to design around 8kb/s speeds which from what I understand is about 4000baud (see edit).

Edit: I was under the impression that 1 baud = 2bps because I saw this wikipedia page http://en.wikipedia.org/wiki/List_of_device_bit_rates . I was wrong.

I just took a couple of minutes to figure out how baud translates to kbps. Turns out, it doesn't.

Back in The Day, 300 baud translated to 300 bits per second, but "as modem technology advanced, compression and other techniques were able to get higher bit per second transfer rates without a corresponding linear increase in state changes. Baud became an outdated term because it wasn’t able to accurately and proportionately express transfer rates, so bps became the standard."[0]

There is some more in-depth information about what "as modem technology advanced" means on Wikipedia[1]. Interesting stuff.

_____

[0] http://www.tech-faq.com/kbps.html

[1] http://en.wikipedia.org/wiki/Baud

rbanffy and ordinary are both right. "Baud" is the number of symbols per second; a symbol can be a specific frequency, or a phase shift, or Complex Electronic Magic. Up through 300 baud, each end used a tone for 0 and a tone for 1, and that was it. One bit = one symbol. (You could hear zeros and ones go by if you listened, and for Commodore owners, it was critical to be able to whistle the answer tone so you could trick the modem into hanging up - it auto-answered every call.)

So each baud carried one bit, and we got used to equating 300 baud with 300 bps. Then came 1200 bps modems, which sent two bits per symbol (four discrete tones, IIRC); they were technically 600 baud modems. It got more complex from there. And thus the confusion began; trying to tell people they had a 600 baud modem was about as useful as trying to tell them it's really called GNU/Linux.

> 300 baud with 300 bps. Then came 1200 bps modems

Nooo, then came 1200-75 asymetric modems - 1200 baud down, 75 baud up - sez the fellie that used to use edlin on the DEC Vax :(

IIRC, baud rate is the number of states you push down the line per second. If you have 1200 baud and 4 different states, you have 2400 bps. IIRC, phone line modems never got much past 9600 baud - what increased was the number of states (I think they were called symbols) you could pass through the line and hence the number of bits per state.

Baudot is also the 5-bit code you see on some paper tapes.

4000 baud is more like 0.5KB/s

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