Switching programs via the keyboard?

[KevRC4130]

Hi everyone,
I'm just wondering if there's a way to change what program is selected (like what name shows up in the top left corner) by any command on the keyboard? Or do I just need to click using the mouse?

Thanks

 

[bousozoku]

Have you tried Command-Tab?

 

[kukheart]

switch programs=command(apple)+tab duh