What does the | operator do? [duplicate]

Answer 1

In Javascript, the | operator is a bitwise operators (in contrast to the || operator which is a logical operator).

It convert each operand to a 32-bit number, and performs a bitwise or between them.

Example of expressions and their results:

1 | 1 === 1
1 | 2 === 3
1.99 | 2.99 === 3

Reference: http://developer.mozilla.org/en/JavaScript/Reference/operators/bitwise_operators

Answer 2

Depends where you use it:

• In regular expression it represents "or": /[a-z]|[0-9]/i
• It is also bitwise or operator, as described in: What does the "|" (single pipe) do in JavaScript?