.AU3 File Extension
What is a AU3 file?
Automated script created with AutoIt v3, a freeware scripting program that uses a programming language similar to BASIC; designed for automating commands within Windows and for other general scripting purposes.
The AU3 file format stores AutoIt3 scripting language. The script can be used to simulate keystrokes, mouse movement, and manipulate windows, which can automate tasks that are not possible with VBScript or SendKeys.
NOTE: You can edit AU3 script files with the SciTE4AutoIt3 program.