Question

I’m just curious what Afx stands for. And what about Fx in FxCop?

Answer 1

From Wikipedia:

One interesting quirk of MFC is the use of ‘Afx’ as the prefix for many functions, macros and the standard precompiled header name ‘stdafx.h’. During early development what became MFC was called ‘Application Framework Extensions’ and abbreviated ‘Afx’. The name Microsoft Foundation Classes (MFC) was adopted too late in the release cycle to change these references.

The old Stingray MFC FAQ (no longer found on their website, link is to ancient version):

In the beginning, Microsoft created a group called the AFX group
(stands for (A)pplication (F)ramework(X)).

[…]

The AFX group was actually responsible for two things: the MFC library and the IDE’s support for MFC (namely, the resource editor and the wizards). The AFX name was dropped in April 1994, and the group’s members simply became part of smaller teams within the Visual C++ group. One of those smaller teams is today’s MFC team.