8.1 · Lesson 1 of 7
Variables, constants and data types
Syllabus 8.1.1Syllabus 8.1.2
What this lesson covers
- Declare and use variables and constants
- Use integer, real, char, string and Boolean data types
Key vocabulary
- Variable
- A named location in memory that stores data, which can change while the program runs.
- Constant
- A named value that can't change while the program runs.
- Identifier
- The name given to a variable, constant, array or subroutine.
- Declaration
- Setting up a variable with an identifier and a data type, e.g. DECLARE Score : INTEGER.
- Assignment
- Storing a value in a variable, using ←.
- Initialisation
- Giving a variable its first value, e.g. Total ← 0.
- INTEGER
- A whole number.
- REAL
- A number with a decimal part.
- CHAR
- A single character.
- STRING
- Zero or more characters.
- BOOLEAN
- TRUE or FALSE.
- Concatenation
- Joining strings together.
Check your learning
- Quick check: 4 questions
- Key vocabulary test: 12 terms
- Activity 1: Valid identifier? · 8 questions
- Activity 2: What data type is it? · 8 questions
- Activity 3: Choose the declaration · 6 questions
- Activity 4: Variables quiz · 8 questions