# Meaning of Program Algorithm

Meaning of Program  Algorithm

A program algorithm is the step by step description of the program. It is a designing tool that explains how a program can be developed or how a problem can be solved by using steps of instructions. It consists of stepwise list of instructions. The designer writes using simple English and mathematical statement.

Example: [find the square of inputted number.]

Step 1: START

Step 2: Input a number N

Step 3: Calculate Square=N*N

Step 4: Display Square

Step 5: END

Explain aims of program design and building blocks of a structured programming

Aims of Program Design

• The major aims of program or system Design are:
• Explain how the system should be developed.
• Identification of reports and outputs of new system.
• Sketch the input screen and layout of menus options.
• Identification of individual data items, database and calculation procedures.

Building Blocks of a structured programming

The building blocks of a structured programming are the control structure. These are sequence, selection, and iteration.

• A sequence is simply a series of procedures that follow one another serially. It does not contain any conditional or looping statements.
• The selection or conditional contains at least a condition and the execution depends on the condition. Different set of statements will be executed depending on the condition.
• Iteration   or looping is an operation that repeats the execution of statement until a certain condition is satisfied.