Brick Block was one of the first original puzzle games that appeared in TI-Basic. The premise of the game is that you are a little plus sign (+), and you want to navigate your way to the big plus sign. In order to do that, however, you need to push and pull the white movable blocks that stand in your way. (You can also use the teleport block to teleport yourself to another location on the board.)
The game is one of the first to feature a decent level editor, which allows you to make your own custom levels and then play them in the game. If you just want to play the game, there are twenty built-in levels available — and they are compressed to take up as little space as possible.
When you get tired of playing, you can quit the game, and it will automatically save where you left off for the next time you play. Since the game keeps a highscore based on how efficient you were (calculated by how long it took you to complete and how many moves you needed), you will most likely be playing it again.