Stardock Groupy is a Windows application that allows you to group open windows together on your taskbar. Instead of having multiple individual icons for every open window of a program, Groupy combines them into a single icon. When you click that icon, a small window pops up showing all the grouped windows, allowing you to quickly switch between them.

Essentially, it enhances the Windows taskbar[SQ]s functionality by providing a more organized and efficient way to manage many open windows, especially useful for multitasking and those who frequently use numerous applications simultaneously. Think of it as a more powerful and customizable version of the default Windows taskbar grouping.