CIFS (Common Internet File System) was an adaptation of SMB- a DOS/Windows/OS/2-specific standard, CIFS was a multi-platform (UNIX, VMS, etc) standard. It was used as a file and printer sharing protocol on various types of systems.

CIFS was optimized specifically to operate efficiently on low-end systems (ie: slow modems, minimal RAM, etc). It was meant to be a supplement to HTTP and to virtually replace FTP as it was "archaic."

Microsoft boasted the ability for multiple users to edit the same file at the same time. The system also allowed anonymous as well as authenticated users to view certain files (depending on permissions, of course) which was highly detailed as "sophisticated" and "secure" by MS.

At one time, CIFS was backed by numerous companies (AT&T, Data General, Digital Equipment, Intel, etc) and they included it in their software (AT&T Advanced Server, Digital Equipment's PATHWORKS, etc). It was vastly overtaking the geek community and it was hard to escape. Notably, CIFS was also bundled with Samba, the popular Linux/UNIX/Windows connectivity standard.

All was going well for our beloved CIFS. That was, until users actually attempted to implement it as a file-sharing server, upon which it went down like an old French whore.