I tried writing a basic program that involved 'while ' loop, but whenever I try running it I get 'time limit exceeded' ,why?

Answer 1

php by default set a time limit for a running script (20 sec i think), this is for not to "block" the server in one task, you can override this directive.

Answer 2

if this behavior it's not intended, check your loop statement, maybe there is a infinite loop.