Beginner tutorials are for people who have never played chess before, or who may have played but are unclear on one or more rules of the game. These tutorials assume no prior knowledge of the game.
Novice tutorials are for players who have only just learned the rules, or more experienced players who have never studied chess seriously before. For players who have ratings, this corresponds roughly to USCF class E and below, a FIDE rating below 1200, or an ECF grade below 80.
Intermediate tutorials are for improving players familiar with basic strategies and tactics, as well as opening and endgame principles. For players who have ratings, this corresponds roughly to USCF class C and D, a FIDE rating between 1200 and 1600, or an ECF grade between 80 and 125