Puzzle gaming here we go.
If you don't catch the blocks with the catching device then they fall into an abyss and after a certain amount have been lost in this way it is game over. The catching device itself can hold as many as five blocks before it can't hold any more (thus rendering any blocks, even in direct line of the catcher, falling into the abyss). These blocks can then be distributed to the bin below or the uppermost block on the catcher can be shunted back onto the conveyor belt to allow some player-control of where and when the blocks can be placed.
There are a hundred levels in the game and progress to the next is determined by the level that you are on. Some levels require a certain amount of points, some ask that you complete a certain amount of diagonal Klaxes while some others demand that you survive a set amount of coloured blocks. Sounds like a mish-mash of columns and tetris? Well yes, I suppose it is but that is no reason to disreguard a worthy puzzler. It is fast, frenetic and easy to pick up. Try it and see for yourself.