What is the purpose of using the exec() function in PHP?

The exec() function in PHP is used to execute an external program or command. It can be used to run shell commands, system commands, or any other executable file on the server. This function is commonly used for tasks such as running shell scripts, executing system commands, or interacting with other programs.

// Example of using exec() function to execute a shell command
$command = 'ls -l';
exec($command, $output);
foreach ($output as $line) {
    echo $line . "<br>";
}