How can PHP be used to start and stop Windows programs?

To start and stop Windows programs using PHP, you can use the `exec()` function to execute commands in the command prompt. To start a program, you can use the `start` command followed by the program path. To stop a program, you can use the `taskkill` command followed by the program name or process ID.

// Start a program
exec('start "C:\Program Files\Program\program.exe"');

// Stop a program
exec('taskkill /IM program.exe /F');