A numeral system with 3 digits: 0, 1 and 2.
The rightmost digit has the value 1, the digit to the left of it has the value 3 (10=3, 20=6). The digits to the left of that are 3*3 (9), 3*3*3 (27), 3*3*3*3 (81) and so on...
Similar to the binary
byte, the
ternary system has
tryte, six ternary digits. There are 729 possible trytes. (compare with 256 possible bytes!)