A computer mouse is a small, handheld pointing device that controls the movement of the cursor on a computer screen and allows users to select text, files, folders, and icons. It detects two-dimensional motion relative to a surface, which is typically translated into the motion of the pointer on a display, allowing for smooth control of the graphical user interface (GUI) . The mouse first became a widely used computer tool when Apple Computer made it a standard part of the Apple Macintosh in the early 1980s. Today, the mouse is an integral part of the GUI of any PC.

A typical mouse has two buttons, a scroll wheel, and a laser sensor. The buttons allow users to select objects and click on buttons, while the scroll wheel enables additional control and dimensional input. Mice can also be used to drag-and-drop objects and give access to the right-click menu.

The earliest known written use of the term mouse or mice in reference to a computer pointing device is in Bill Englishs July 1965 publication, "Computer-Aided Display Control". The popularity of wireless mice without cords makes the resemblance to a mouse less obvious.

There are different types of computer mice and pointing devices used with a computer, including optical, mechanical, touchpad, trackball, and air mouse. Optical mice are the most common type of mouse for desktop computers, while touchpads are the most common type for laptop computers.

In summary, a computer mouse is a handheld hardware input device that controls the movement of the cursor on a computer screen and allows users to select text, files, folders, and icons. It is an integral part of the GUI of any PC and has become an essential tool for computer interaction.