Lesson 6 is the sixth level in Chip's Challenge 1. This lesson level introduces invisible walls, hidden walls, and blue walls, plus the possibility of extra computer chips. (The four chips on the left can be collected, but the four on the right cannot; however, only four are required.) To complete the level, move 3L 4U 3L D, which opens the single fake blue wall and allows Chip to take the four chips below. Come back the same way and exit.