Move:

WASD keys.

Aim / Shoot:

Use your mouse.

Change Weapon:

1 - 4 keys.

Reload:

R key.

Drop Weapon:

G key.

Save Game:

Q key.

Buy items:

B key when near shop girl.

Talk to NPC:

Spacebar key.

Get in the car:

Spacebar key.

Game Menu:

M key.