"Chicago" is the codename for the Windows 95 early builds and betas. Build 81 was released in January 1994 and it is a "preliminary release", which came before beta testing, which is where percieved to be completed components are tested by selected individuals at special testing sites.

As with build 56, the splash screen flashes multicolored Windows logos around.

This is the default desktop you will see when the system starts up.
Being such an early pre-beta, however, it is very temperamental and may fail to work/install correctly.

Some of the icons look more primitive than the final icons as well. Note the presence of a Programs folder directly on the desktop, as well as the >> located in the My Computer and Network names.

Although the right-click Display Properties option exists, the dialog box is very different than the final release.

As of B81 the three individual menus have been merged into one start menu filled with everything.

Also note the presence of new 32-bit versions of Windows 3.x applications that will not run on Windows 3.1+Win32s or Windows NT because they make use of new 32-bit APIs not present in either instance.