Rax means Barracks, it is used as a short hand by people discussing the game

A build order is a term used in RTS games, and, refers to how you spend your initial starting cash.

What you spend this money on significantly impacts how you play the rest of the game from that point on. There should be no single perfect build order,but this all depends on how well the game is ballanced.bInstead, there should  be a variety of build orders and many subtle variations of each that can be used. A build order is literally the order in which you build things.

From this order you should be able to tell what strategy your opponent will be using, likewise, if you can see what your opponent is building, you can predict what he is planning to do, and you can adapt to counter it accordingly

This is the start to what i hope will have no end.

Please enjoy, if you dont see what your looking for, let us know!