In Windows operating systems, the Start Button is a central launching point for all the applications on the computer.
Considering its function is very important, it is also very frequently used, and some might eventually get bored with its appearance.
This is why some developers have created alternative start buttons, also called orbs, which try to match various desktop themes.
There are specialized software applications that enable users to customize their start button with a few mouse clicks and replace it with one they might have designed.