These simple scripts redraw the current window to different spaces of the screen (i.e. left or right half of the screen, or full screen). They esentially serve the same functionality windows provides by sliding the window into the side of the screen (and then the window resizes to take up that half of the screen). I don't know the official name for this.
##Use aptivate to assign shortcuts! I like to use aptivate to assign shortcuts to the scripts. I personally use vim-like bindings. For example I've mapped "ctrl+opt+cmd+h" to the lh script.