Meaning of Computer Hardware

Computer hardware refers to the physical components of a computer that can be seen & touched by the user. Hardware is one of the basic and necessary parts of a computer system. Computer hardware also includes communication bus, ports, input device, an output device, etc
Some commonly used input devices are
Keyboard, Mouse, Joystick, smart card reader, microphone, biometric sensor. 
The mouse was invented by Douglas Engelbart at Stanford research center in 1963.