Bit-wise AND and a normal AND

Question

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Why '&&' and not '&'?

When would I use a bit-wise AND and normal AND?

I read the bit-wise AND is good for applications that have a memory limit.

Which one will be the best to use then, overall?

if (true & false)
{

}

or

if (true && false)
{

}

Wouldn't it be better to always use a bit-wise AND then?

"I read the a Bit-wise AND is good for applications that has a memory limit." - where have you read that? That sounds like utter nonsense to me. — Daniel Hilgarth, Apr 19 '12 at 12:36
`true & false` is _not_ a bitwise AND. `1 & 3` is a bitwise AND. — Henk Holterman, Apr 19 '12 at 12:38
@HenkHolterman: It is still a bitwise AND that is happening. The full-eval thingy is only a side effect, because it needs to evaluate all operands to be able to perform the bitwise AND. — Daniel Hilgarth, Apr 19 '12 at 12:51

score 1 · Accepted Answer · edited May 01 '18 at 22:42

Bitwise AND (&) is a bitwise operation on both operands. && instead, is a logical AND operation.

I read the bit-wise AND is good for applications that have a memory limit

This assumption is not correct. I can say that bitwise can be used in intensive calculus, for example in a CAD application kernel's drawing procedure when you need to divide an absolute number by 2 (say), instead of using ordinary division which is slow, we use bitwise shift >>. But these are extreme conditions and 99% of cases none will approve use of such techniques.

So it's basically about performance improvement and not memory.

They are completely different.

Bit-wise AND and a normal AND

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