Random number is generated by using the function rand(),mt_rand(). If the function is used without sending a parameter, a random number between 0 and RAND_MAX is returned.
Ex. echo rand();
To return a random number between 120 and 200 inclusive, the code snippet is
echo rand(120,200);
For returning a random number using the Mersenne Twister algorithm, use mt_rand().
The function srand() is used to seed the random number, and it must be used once in a script and before the rand() function. If the randomness of the seed is greater, more random numbers can be generated.
Ex.
srand((double)microtime()*1000000);
echo rand(0,100);
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