3.1.1.6 Constants and variables in a programming language.

Question 1

Define a constant.

Answer 1

Data values that stay the same every time a program is executed. Constants are not expected to change and can not be overwritten later in the program.

Question 2

Define a variable.

Answer 2

A variable is a memory location, with a name that is associated with that location and are used for holding data.

Question 3

Outline the differences between a variable and a constant.

Answer 3

A constant does not change its value over time. A variable, on the other hand, changes its value dependent on the equation and can change during the programs execution.

Question 4

Outline the advantages of using named constants.

Answer 4

• There is no need to repeatedly type the same value.
• Only at one place the value of the constant needs to be updated in order to change it.
• It makes programs easily readable.