xeyes

Xeyes is a simple command-line tool in Linux that creates a pair of eyes that follow the mouse cursor on the screen. It is a part of the X Window System, a graphical framework for Unix-like operating systems. Xeyes provides a playful and interactive visual representation of the mouse movements. When the cursor moves, the eyes created by the tool also move accordingly, giving the illusion of being watched.

Xeyes was originally developed by Keith Packard and introduced in X Version 11, commonly known as X11. It has become a popular and well-known tool among Linux users due to its simplicity and entertainment value. The functionality of xeyes has not changed significantly over time but continues to be included in many Linux distributions.

While its primary purpose is amusement, xeyes also demonstrates some capabilities of the X Window System. The tool showcases the X11 protocol's ability to track the mouse cursor and update the graphical representation in real-time. The source code of xeyes is freely available, allowing users to modify or enhance its behavior as per their preferences and needs.

Overall, xeyes is a lighthearted and charming command-line tool that adds a touch of whimsy to the Linux environment while highlighting some aspects of the X Window System.