From the Game Manual:
In the computer fantasy world of TRON, the power-hungry Master Control Program (the MCP) seeks to control the human race. You are Flynn, the daring, young programmer, transported into the heart of the computer, to find and disable the MCP.
MAZE-A-TRON is played in ROUNDS. Each round consists of two PHASES--the Circuit Maze (Phase I) and the Master Control Program (Phase II). Each time you complete both phases of a round, you automatically advance one GAME LEVEL.
Game Level affects both DIFFICULTY and SCORING. Difficulty increases with each level up through Level 12. Scoring increases with each level up through Level 99.