Introduction for computer work and how it work , Firstly how a computer make a computer then how information is represented using electricity next how computer use circuits. description of computer parts and see how software controls hardware. A computer make a computer in 4 part (input,storage,processing and output). input like camera,mouse..etc. . storage : is a information from input and stored in memory. processing : take the information from memory and manipulate or change it using an algorithm . output can be multiple thing like display or signal or information..etc. Description of bit and how can be huge to represent complex information. Description of the binary number system and differences between decimal number system and binary number system . decimal have 9 digit from 1 to 9,binary have two digit : 0 , 1 . discussed how the text , image and sound can be in binary number system. discussed the old computer was very big and very slow unlike today the computer is small and very fast because the circuit now smaller. Memory stored information, CPU take this information and calculate the binary stored it in memory, Finally this information is sent in binary to output and these processing steps doesn’t take any time. CPU could be a connection between hardware and software , when CPU receives a command it deal with it as required and store it in the hardware in the appropriate place. OS is a program that manages how software uses the hardware of a computer.