A lot of software advertises itself as working with a Hayes modem or Hayes compatible modem. What does that mean? And what’s Hayes? It’s a de facto standard named after a defunct maker of modems. Let’s talk about why Hayes was important. It was so important, you can even still buy a USB Hayes compatible modem for legacy applications today.
Hayes introduced a command set that started with the letters AT, for ATtention. Other makers adopted this command set and cloned the Hayes modem to various degrees, leading to the terminology of a Hayes compatible modem.

David Farquhar is a computer security professional, entrepreneur, and author. He has written professionally about computers since 1991, so he was writing about retro computers when they were still new. He has been working in IT professionally since 1994 and has specialized in vulnerability management since 2013. He holds Security+ and CISSP certifications. Today he blogs five times a week, mostly about retro computers and retro gaming covering the time period from 1975 to 2000.










