Variable Declaration & Assignment
Computer Science: OCR GCSE, topic 2.2.1
Variable Declaration and Assignment
A variable must be declared before a value can be assigned.
Declaration
- Before variables can be used, they must be declared.
- Declaring a variable means telling the computer:
- What the identifier (name) should be.
- What type of data will be stored.
Assignment
- Changing the value stored inside a variable is called assignment.
- The value assigned to a variable must match the data type of the variable.
Language specifics
- Some languages don’t need you to declare variables before you use them:
- These languages automatically declare the variable before the first assignment.
Test yourself on Variable Declaration & Assignment
All languages require variables to be explicitly declared. True or false?
What is important to check when assigning a value to a variable?