Space Invaders is a game where you destroy primitive aliens, you eliminate them as thay descend.
Press start and use the mouse to fire the laser in the combat zone. Anyone over 25 will know this game.

Alien Basic	10 points	After 300 points, Alien Rapide starts
Alien Rapide	50 points	After 400 points, Alien Mobile starts
Alien Mobile	80 points	After 500 points, Alien Paralyser starts
Alien Paralyser	100 points	After 1000 points, Guardian Angel starts
Guardian Angel	0 points