1	Hardware Basics: Inside the Box
2	Chapter Outline
3	What Computers Do
4	What Computer Do
5	Input Devices Computers accept information from the outside world
6	Output Devices Computers produce information and send it to the outside world. A video monitor is a common output device.
7	Process Information The processor, or central processing unit (CPU), processes information and performs all the necessary arithmetic calculations.
8	Store Information Memory and storage devices are used to store information
9	"Input devices" Input devices
10	Information Information comes in many forms
11	A Bit About Bits A bit (binary digit) is the smallest unit of information can have two values can represent numbers, codes, or instructions
12	More about Bits Each switch can be used to store a tiny amount of information, such as: An answer to a yes/no question A signal to turn on a light
13	Bits as Codes ASCII - American Standard Code for Information Interchange most widely used code, represents each character as a unique 8-bit code.
14	Bits as Instructions The computer stores programs as collections of bits. For instance, 01101010 might instruct the computer to add two numbers.
15	Bits, Bytes, and Buzzwords Common terms might describe file size or memory size:
16	Bits, Bytes, and Buzzwords MB: (megabyte): about 1 million bytes of information GB: (gigabyte): about 1 billion bytes of information TB: (terabyte): about 1 million megabytes of information
17	The Computer’s Core: The CPU and Memory The transformations are performed by the CPU - the central processing unit or processor.
18	The CPU: The Real Computer When purchasing a computer, selecting a CPU is very important. The two most critical factors are:
19	Compatibility Not all software is compatible with any given CPU. Each computer has a unique instruction set - a vocabulary of instructions the processor can execute. New microprocessors can usually run older software, but new software is not usually compatible with old microprocessors.
20	Speed The computer’s speed is measured by the speed of its internal clock - a device to synchronize the electric pulses.
21	Speed A computer’s speed cannot be judged by megahertz alone.
22	Speed
23	Speed Parallel processing places multiple processors in a computer. Most supercomputers have multiple processors that divide jobs into pieces and work in parallel on the pieces.
24	The Computer’s Memory RAM (random access memory):
25	The Computer’s Memory ROM (read-only memory):
26	Buses, Ports, and Peripherals Information travels between components through groups of wires called buses.
27	Buses, Ports, and Peripherals Busses also connect to slots inside the computer as well as
28	Buses, Ports, and Peripherals Slots and ports also allow external devices called peripherals to be added to the system (keyboard, monitor, and mouse).
29