Data types

Each must have a data type. The data type determines what type of value the variable will hold.

Data type	Purpose	Example
Integer	Whole numbers	27
Float	Decimal numbers	27.5
Character	A single alphanumeric character	A
String	One or more alphanumeric characters	ABC
Boolean	TRUE/FALSE	TRUE

Data type	Integer
Purpose	Whole numbers
Example	27

Data type	Float
Purpose	Decimal numbers
Example	27.5

Data type	Character
Purpose	A single alphanumeric character
Example	A

Data type	String
Purpose	One or more alphanumeric characters
Example	ABC

Data type	Boolean
Purpose	TRUE/FALSE
Example	TRUE

Different data types have limitations:

integers and floats cannot be concatenated, ie joined together
numbers held in strings cannot be subject to mathematical operations

Casting

Sometimes a programmer needs to change the data type of a variable. For example, an integer may need to be converted to a string in order to be displayed as part of a message. This process is known as casting. The following examples convert a string to an integer and an integer to a string:

str(68) returns “68”
int(“54”) returns 54

Programming fundamentals - OCRData types

Data types

Casting

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