Types of Data

Single pieces of data are called data items. A data item can fall into three main categories of data type.

Name Graphic Description
Numeric  Numbers There are two main numeric data types: Integer and Real. Integers are positive and negative whole numbers, i.e. numbers without a decimal point, for example: 19, 0, -78. Real, or floating point, are numbers with fractional parts, i.e. with a decimal point, for example: 112.5, -0.42, 3.1495
Character  Characters The character data type can be thought of in terms of two sub-categories: single characters and strings of characters. A single character could represent a single number, an alphabetic character, a punctuation mark, mathematical symbol, or a special symbol, for example: ‘+’, ‘A’ and ‘£’. Note: Characters and Strings are usually enclosed in quotation marks when used by a programming language.
Logical (Boolean) Boolean On and Off The logical (or Boolean) data type is characterised by data that can only take the values True (On) and False (Off).

Data Type Flash Cards

  • A whole number


  • Number with decimal place


  • True or False only


  • A single letter


  • Multiple characters






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