Scalars are numbers that are used to measure size, or how big or small something is. They represent the magnitude of a quantity such 12.5 miles, or 34 degrees C.

Numbers that are not scalars

  • Counting numbers

    Numbers that are used to count things are not considered scalars, although you can do arithmetic with them. For example 2 apples + 3 apples = 5 apples.
    For more see Counting numbers.

  • Identifying numbers

    Identifying numbers are not scalars and are used to identify something or act as an identifying label. For example a phone number, or student id number are not scalars. You cannot do arithmetic with them. For example, dividing a phone number by three has no meaning.

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Other number topics

Scalar numbers

Counting numbers

Numbers that have factors

Special values