In most modern programming langues, there is a variant of while.
while is a keyword to create a loop, where generally the syntax is something like this:
while ([condition])
[expression]
Which is to say, that as long as [condition] evaluates to true, [expression] (or the body of the loop) is kept executed over and over again.
The following C code counts backwards before a rocket is launched.
#include <stdio.h>
int main()
{
printf("Rocket is launched in...\n");
int seconds = 5;
while (seconds > 0)
{
printf("%d...\n", seconds);
seconds--;
}
printf("Ignition!\n");
return 0;
}
The while loop terminates, when seconds will not be larger than zero anymore.