C, C++, Prolog. The ANSI versions because it is cheaper. ISO standards are expensive. Standards could be very precise and effective in providing information but the experience varies wildly. I like RFCs which I find quite readable.

Not personally, but I worked in manufacturing and the company bought them.

The company is required to adhere to ISO and other certifications specified by the customer. In order to adhere to the standards, you need to have the current revision of the standards. If in your annual audit it's determined that you don't have the current revision, that's a non-conformance. Correct it by purchasing the new version.

Also, you need to pay for the "official training" before you start to get certified. And you need to pay for "internal auditor training" as part of the requirements.

ISO 9000 series, IATF 16949 series, ISO 14000 series, some welding ones, painting ones, ASME standards for drawings, Y14, IIRC.

And the Automotive Industry Action Group's (AIAG) "Core Tools" series of books. I don't think they are standards, but they are "customer requirements", which means you can't be certified without them. They are used for new product introduction, so you can't pass new part submission without following the rules in them.

I have been given bound paper copies of ones that I wrote.

Can also download PDFs of any that would be useful in developing new standards, I don't need to buy them.

I wanted a copy a couple of times per year, but never considered buying. With some exceptions, they are available elsewhere as a gratis download. All hail https://enwp.org/Libgen https://enwp.org/Z-Library

Most recent one was ISO 9, just to satisfy curiosity.

Can’t think of any ISO standard off the top of my head, but there’s a few standards I’ve looked at purchasing before. Particularly IEEE, but some of those can be very expensive.

A lot of the standards I look at are ITU or from some independent vendor available for free or at a low cost.

I have a copy of ISO 27002 from my employer: https://en.wikipedia.org/wiki/ISO/IEC_27002

It is kinda nice to be able to literally throw the book (or at least screenshots of the book) at management when they don't want to take security seriously.

25237, Health informatics — Pseudonymization

AMA