Team-based shooter by Valve that's pretty pro.
Go get it on steam for free.
A compilation of the "Meet the [class name]" short videos Valve puts out. Well worth your time~
- Spoiler:
- [Meet the Engineer, Meet the Soldier, Meet the Demoman, Meet the heavy, Meet the Sandvich, Meet the Scout and Meet the Sniper]
And the newer Meet the Medic: