This web site hosted the PC/SC specification. This specification is implemented as WinSCard API for Windows and pcsc-lite on Unix.
PC/SC is the standard way to access smart card readers and smart cards from a Windows of Unix system.
See "PC/SC sample in different languages" for some examples.
Last days
The death of the web site was not announced on any PC/SC mailing list I know.The latest meeting of the PC/SC members was in December 2016.
The latest email I received from the pcscmembers mailing list was in January 2018.
I guess the group went out of money (not enough paying members) and the company managing the website and meetings (at a very high price) just stopped providing services.
The PC/SC specification are mature enough, or PC/SC members just moved to something else?
It is important to note that Windows never implemented the latest version of PC/SC v2 part 10 (to support pinpad readers in the Windows CCID driver for example). So working on a specification that is not implemented by the major provider is somewhat useless.
Web site copies
The web site was still available the 9th of January 2019 and it has been archived by the Internet Archive (Wayback Machine) at https://web.archive.org/web/20190109211601/https://www.pcscworkgroup.com/The specification files are also available from the Internet Archive at https://web.archive.org/web/20170904222045/https://www.pcscworkgroup.com/specifications/download/
PC/SC specifications copies
I decided to host a copy of the PC/SC specification documents on https://muscle.apdu.fr/www.pcscworkgroup.com/.I used the copies I made for my own use. But now that the official web site is down I make them public.
Conclusion
It is sad to see a website to disappear silently with no warnings.If you have other PC/SC public documents you want to share just tell me.