Numbers and Strings, Arithmetic Operators

The + (Addition) operator is used for both addition and string concatenation; numbers are added, strings are concatenated. Therefore, if one of the operands of the addition is a string, the result will be a string.

'a' + 10

The result will be the string 'a10'.

'1' + 10

The result will be the string '110'.

20 + 10

The result will be number 30.

All other arithmetic operators */-@ (multiplication, division, subtraction and remainder) support numeric strings. Meaning, that if one of the operands is a numeric string it, will be automatically converted to a number.

Examples

20 / '10'

The result will be 2.

20 / 'a'

The result will be [Undefined].

tip

Remember that the addition operator concatenates strings. Example:

'my' + 10

The result will be the string my10.