& and && - (nf)

[utzoo!decvax!harpo!floyd!vax135!ariel!orion!lime!houti!hogpc!houxz!ihnp4!ixn5c!inuxc!pur-ee!uiucdcs!donchin]

#R:uiucdcs:27600015:uiucdcs:27600017:000:363
uiucdcs!donchin    Mar 23 22:56:00 1983

&& works as follows:
	0 && a == 0        (for all 'a')
	a && b == 1        (for all a!=0 and b!=0)

& is a little bit more complicated:
	The two operands are compared bitwise, and the result
bit in the same position is set if both operands have 1 in that
position, cleared otherwise.

	This means that & works like &&, but on a bitsize instead
of wordsize scale.