RNG and time(NULL) vs time(0)

[asrockw7]

is there another/better way to generate random numbers aside from:

srand(time(NULL));
x = rand();

that is comprehensible enough for a beginner?

also, what's the difference between using time(NULL) and time(0) in srand()?

[hamsterman]

Is anything wrong with sradn(time(0))?
NULL is 0. There is no difference between them.

[Abramus]

rand() doesn't generate random numbers. It generates PSEUDO-random numbers. Computers are not actually able to generate real random numbers, they can only generate sequences of values that seem random. Quality of this pseudo-randomness depends on the algorithm used. rand() uses very simple algorithm thus it is fast, but generates a poor quality sequence where dependencies between elements of the sequence can be easily found. Nevertheless, for many cases (like simple games, or whatever a beginner could make) it is sufficient. It is not sufficient for example in cryptography, where it is critical to have the highest possible quality of a pseudo-random sequence.

As for your second question, in C++ NULL is defined to 0, so go figure the difference.