A computer mouse is small computer device that we connect to our computer, invented by Douglas Engelbart in 1963 and one of the great breakthrough that changed how people interact with computers. Mouse is considered as an input device and most often used with personal computers. A computer mouse is derived from its shape and because the wire connected to the mouse can be imagined as its tail. With the use of a mouse we can easily interact with windows and other computer programs that a computer keyboard can't normally do.
Moving your computer mouse on a flat surface will move the mouse pointer on your screen the same direction as where you move your computer mouse. A typical computer mouse consists of at least two buttons one located on the right side and the other to the left side. The right button of a mouse is usually used for option menu of a particular program ("e.g MS Word"). Whenever you right click on any portion of the screen and for instance that particular portion of the screen has an option menu that menu will popup. The left button of a mouse is usually used for selection. Newer computer mouse have scroll wheel used for scrolling the screen of a particular program ("e.g MS Word") up or down this is useful if the program you are using have vertical scroll bar. Most often vertical scroll bar are shown when the screen of a particular program does not fit into the computer display. Modern computer mouse have more than two buttons, the functions assigned to the other buttons will depend on the manufacturer specification.
Most commonly used type of mouse are the mechanical mouse, optical mouse and the wireless mouse. A mechanical mouse houses a hard rubber ball that rolls when you move the mouse. As the ball move the horizontal and vertical wheel moves. The LED and photodiode act as sensors, since the wheel have holes on it the beam of light that the LED emits breaks on and off which turns as pulses. The speed of the mouse pointer that you see on your screen is directly proportional to the speed of pulses that the sensors generate.
Optical mouse uses light emitting diode (LED) that bounces off the surface to a CMOS sensor chip in order to detect movement. Optical mouse don't have moving parts that will likely to worn out over time.
Wireless mouse is another kind of computer mouse and are more advance than the mechanical and optical computer mouse. Wireless mouse uses Radio Frequency usually on a 2.4GHz frequency and runs on battery. These kinds of mouse have a receiver that usually plug into the computer in the form of a USB device or an add-on card that is placed in an expansion card inside your computer.