AutoHotKey

AutoHotKey is a free, open-source scripting language for Windows that allows users to easily create small to complex scripts for all kinds of tasks.

I use it for fixing issues with swapping Ctrl and Alt key bindings after using SharpKeys to remap them to a Mac-style layout. See My Windows 10 Setup for context on why the swap is needed, and AutoHotKey Script for the script itself.

Use the script syntax cheatsheet to understand the scripting language.