Differentiate among various styles of system units on desktop computers, notebook computers, and mobile devices. Desktop Computers Electronic components and most storage devices are part of the system unit.

Other input and output devices are outside the system unit. With the exception of all-in-one desktop which houses the monitor and system unit In the same case. Notebook Computers The keyboard and pointing device often occupy the area on the top of the system nit.The display attaches to the system unit by hinges. On a Tablet PC, the system unit is located depending on the design of the device. Mobile Devices The system unit on mobile devices usually consumes the entire device.

The display is built into the system unit. 2. Describe the control unit and arithmetic logic unit components off processor, and explain the four steps in a machine cycle. Control unit Arithmetic Logic unit 2-Decode 1 -Fetch 3-Execute 1 OFF Memory The control unit directs and coordinates most of the operations in the computer - a role much like a traffic cop.

The arithmetic logic unit performs arithmetic, comparison, and other operations. The operations include basic calculations such as addition, subtraction, multiplication, and division. The Machine Cycle repeats a set of four basic operations. First, is to obtain the program instruction or data item from memory (1 -Fetch). Then, translate the instruction into signals the computer can execute (2-Decode) and carry out the commands (3-Execute).

Last, is to write the result to memory (4-Store).