|Numeral systems by culture| |Positional systems by base| |Non-
standard positional numeral systems| |List of numeral systems|
The numerals are made up of three symbols; zero (shell shape),
one (a dot) and five (a bar). For example, thirteen is written
as three dots in a horizontal row above two horizontal lines
stacked above each other. Numbers above 19  Numbers after 19
were written vertically in powers of twenty. For example,
thirty-three would be written as one dot above three dots, which
are in turn atop two lines. The first dot represents "one
twenty" or "1×20", which is added to three dots and two bars, or
thirteen. Therefore, (1×20) + 13 = 33. Upon reaching 20^2 or
400, another row is started. The number 429 would be written as
one dot above one dot above four dots and a bar, or (1×20^2) +
(1×20^1) + 9 = 429. The powers of twenty are numerals, just as
the Hindu-Arabic numeral system uses powers of tens. Other than
the bar and dot notation, Maya numerals can be illustrated by
face type glyphs or picture