Space Invaders is a classic arcade style game. The aim of the game is to destroy the invaders by firing at them. Beware that there are three types of opponents. What you need are concentration and good reactions.
The ships of the space invaders, aligned in rows, are moving leftwards/rightwards across the screen. Each time the enemies come to the end of the window all rows get one step closer to your position. Your aim is to fire at the invaders until you destroy them. At the bottom of the screen there are several groups of asteroids that protects you from the invaders' fire. Each time you or your enemy hit an asteroid it gets "broken". When the asteroid is hit at the same place for the second time, it becomes cracked and you gets more vulnerable. At the start of each game you have three lives. Be aware of the fact that there are three types of enemy ships.
A flying object called "bonus ship" passes the upper part of the game board during certain periods of time. If you hit it, you can get a bonus. There are 5 kinds of bonuses.