Grow and shrink the squares to clear them by forming chains of 3 or more of the same size and color. You can build longer chains by rapidly clicking on adjacent squares. Create combos (chain reactions) and get bonus score. If all 6 blocks in a row are same- all blocks on screen of that color are destroyed. This also gives you magic erasers, that you can use to remove single squares. Right-click or hold down Control to Quick-remove squares.
Windows Server 2008