With the indulgence of the other posters.
The Acer Aspire AST180-UD400B or better known as Aspire T180 comes with a standard keyboard as shown below
Should this be what you have, the basic keys on the top left are:
Esc - Escape key. It is basically a shortcut to STOP or get out of a program sequence. Often this is as a shortcut key for the Stop button in many web browsers
F1 - usually launches a program's Help Guide
F2 - usually launches Rename command
F3 - usually launches Find or Search command
F4 - formerly a DOS for launching previous OS but currently used in conjunction with Alt that closes an active, open window and/or exits a program. With no active, open windows, it prompts you to exit.
If for some reason your keyboard is different, it is possible that the dealer could have bundled a different/after market keyboard such as those web or multimedia as shown below. The top left keys then would be either for web browser shortcut keys or multimedia shortcut keys or some other specialized functions.
Should this be the case, pls post back with the brand/model which may be determined by looking at the bottom or any of the markings at the top.
Hope this be of additional help/idea. Pls post back how things turned up or should you need additional information.
Good luck and kindest regards.