Bitwise union (or)
The bitwise union or produces a result by comparing all 64 bits of its left and right operands, which must be expressions of type integer, one bit at a time. For each bit in the two operands, the corresponding bit in the result value is set to 1 if either or both operands bit values is 1 and set to 0 if both operand bit values are 0.
Example
The following table illustrates this using 64-bit binary values.
|  a := 42;
 | 0000000000000000000000000000000000000000000000000000000000101010 | 
|  b := 642;
 | 0000000000000000000000000000000000000000000000000000001010000010 | 
|  a or b
 | 0000000000000000000000000000000000000000000000000000001010101010 |