Base-3 (also called ternary or trinary) number system uses three symbols to code information. Most commonly, these symbols are, 0, 1 and 2.
Base-36 number system uses 36 symbols to code information. Most commonly, these symbols are, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, and 'A to Z' (or alternatively 'a to z').