Variables, Constants & Assignments (Edexcel GCSE Computer Science)

Variables, Constants & Assignments

What is a variable?

• A variable is a named memory location that holds data that during the execution of a program, the data can change

• Variables can store a variety of different types of data such as numbers, text or true/false values

• To store data in a variable, the process of assignment is used

What is a constant?

• A constant is fixed data that during the execution of a program cannot change

• A constant can store a variety of different types of data, similar to variables

• Pi is an example of a mathematical fixed value that would typically be stored as a constant

What is assignment?

• Assignment is the process of storing data in a variable or constant under a descriptive name

• Assignment is performed using the '=' symbol

Assigning variables & constants

Data Types

What is a data type?

• A data type is a classification of data into groups according to the kind of data they represent

• Computers use different data types to represent different types of data in a program

• The basic data types include:

• It is important to choose the correct data type for a given situation to ensure accuracy and efficiency in the program

• Data types can be changed within a program, this is called casting