[int] Difference between int and double

I was wondering if someone could tell me why anyone would use int instead of double? It seems to be that double is much more flexible than int.

Thanks

Operations on integers are exact. double is a floating point data type, and floating point operations are approximate whenever there's a fraction.

double also takes up twice as much space as int in many implementations (e.g. most 32-bit systems) .

int and double have different semantics. Consider division. 1/2 is 0, 1.0/2.0 is 0.5. In any given situation, one of those answers will be right and the other wrong.

That said, there are programming languages, such as JavaScript, in which 64-bit float is the only numeric data type. You have to explicitly truncate some division results to get the same semantics as Java int. Languages such as Java that support integer types make truncation automatic for integer variables.

In addition to having different semantics from double, int arithmetic is generally faster, and the smaller size (32 bits vs. 64 bits) leads to more efficient use of caches and data transfer bandwidth.

Short answer:

int uses up 4 bytes of memory (and it CANNOT contain a decimal), double uses 8 bytes of memory. Just different tools for different purposes.

int is a binary representation of a whole number, double is a double-precision floating point number.