Performs a bitwise OR on two expressions.
result = expression1 | expression2
The | operator looks at the binary representation of the values of two expressions and does a bitwise OR operation on them. The result of this operation behaves as follows:
0101 (expression1) 1100 (expression2) ---- 1101 (result)
Any time either of the expressions has a 1 in a digit, the result will have a 1 in that digit. Otherwise, the result will have a 0 in that digit.