Remove enough bricks to pass to the next level. There's various kinds of bricks by their colors and drawings, try to hit them to find their properties. You'll also find special eggs, that you can use for special purposes and fill your power bar. The game includes 40 levels and a very comprehensive level editor, where you can create your own levels.
Move the mouse to aim and keep pressed the left mouse button to give power to the shot; release it to shoot. In the level editor you interact with mouse clicks.