What potential issues can arise when using the sleep() function in PHP to delay execution?

One potential issue when using the sleep() function in PHP to delay execution is that it can pause the entire script, causing other processes to wait. To solve this issue, you can use the usleep() function instead, which delays execution in microseconds without pausing the entire script.

// Using usleep() to delay execution without pausing the entire script
usleep(1000000); // Delay for 1 second
echo "Delayed execution without pausing the entire script.";