Computer Programming 13278 GENG 106 L02

Program/Software

A program is a set of instructions that a computer follows to perform a task.

Programmer/Software Developer

A programmer is a person with the training and skills necessary to design, create and test computer programs.

Examples of hardware

CPU, main memory, secondary storage devices, input devices, output devices.

1.2

Computer Systems: Hardware and Software

Main Memory (RAM - Random Access Memory)

Computer's work area. This is where the computer stores a program while the program is running, as well as the data with which the program is working.

Hardware

Hardware refers to the physical components of which a computer is made.

CHAPTER 1

INTRODUCTION TO COMPUTERS AND PROGRAMMING

Bit (binary digit)

In most computer systems, bits are tiny electrical components that can hold either a positive (on) or a negative charge (off).

Secondary storage

Secondary storage is a type of memory that can hold data for long periods of time, even when there is no power to the computer. Programs are normally stored in the secondary memory and loaded into main memory as needed.

1.1

Why Program?

Byte

A computer's storage location is divided into tiny storage locations known as bytes. One byte is enough memory to store only a letter of the alphabet or a small number. Each byte is divided into eight smaller storage locations known as bits.

CPU

The CPU is the part of a computer that actually runs programs. The CPU is the most important component in a computer because without it, the computer could not run software.

Fetch

The CPU's control unit fetches, from main memory, the next instruction in the sequence of program instructions.

Arithmetic and logic unit

The arithmetic and logic unit is designed to perform mathematical operations.

Control unit

The control unit coordinates all of the computer's operations. It is responsible for determining where to get the next instruction and regulating the other major components of the computer with control signals.

Decode

The instruction is encoded in the form of a number. The control unit decodes the instruction and generates an electronic signal.

Execute

The signal is routed to the appropriate component of the computer (such as the ALU, a disk drive, or some other devices). The signal causes the component to perform an operation.