or() -- arithmetic or, used for bit-operations

x=or(a,b) 

Used to compute the bitwise or of both its argument. Both arguments are treated as binary numbers (i.e. a series of 0 and 1); a bit of the resulting value will then be 1, if any of its arguments has 1 at this position in theirbinary representation.
Note, that both arguments are silently converted to integer values and that negative numbers have their own binary representation and may lead to unexpected results when passed to or.

print or(14,3) 

This will print 15. This result is clear, if you note, that the binary representation of 14 and 3 are 1110 and 0011 respectively; this will yield 1111 in binary representaion or 15 as decimal.