<P> The basic unit in the Maya calendar was one day, or k'in, and 20 k'in grouped to form a winal . The next unit, instead of being multiplied by 20, as called for by the vigesimal system, was multiplied by 18 in order to provide a rough approximation of the solar year (hence producing 360 days). This 360 - day year was called a tun . Each succeeding level of multiplication followed the vigesimal system . </P> <Table> Long Count periods <Tr> <Th> Period </Th> <Th> Calculation </Th> <Th> Span </Th> <Th> Years (approx .) </Th> </Tr> <Tr> <Td> k'in </Td> <Td> 1 day </Td> <Td> 1 day </Td> <Td> </Td> </Tr> <Tr> <Td> winal </Td> <Td> 1 x 20 </Td> <Td> 20 days </Td> <Td> </Td> </Tr> <Tr> <Td> tun </Td> <Td> 18 x 20 </Td> <Td> 360 days </Td> <Td> 1 year </Td> </Tr> <Tr> <Td> k'atun </Td> <Td> 20 x 18 x 20 </Td> <Td> 7,200 days </Td> <Td> 20 years </Td> </Tr> <Tr> <Td> bak'tun </Td> <Td> 20 x 18 x 20 x 20 </Td> <Td> 144,000 days </Td> <Td> 394 years </Td> </Tr> <Tr> <Td> piktun </Td> <Td> 20 x 18 x 20 x 20 x 20 </Td> <Td> 2,880,000 days </Td> <Td> 7,885 years </Td> </Tr> <Tr> <Td> kalabtun </Td> <Td> 20 x 18 x 20 x 20 x 20 x 20 </Td> <Td> 57,600,000 days </Td> <Td> 157,700 years </Td> </Tr> <Tr> <Td> kinchiltun </Td> <Td> 20 x 18 x 20 x 20 x 20 x 20 x 20 </Td> <Td> 1,152,000,000 days </Td> <Td> 3,154,004 years </Td> </Tr> <Tr> <Td> alawtun </Td> <Td> 20 x 18 x 20 x 20 x 20 x 20 x 20 x 20 </Td> <Td> 23,040,000,000 days </Td> <Td> 63,080,082 years </Td> </Tr> </Table> <Tr> <Th> Period </Th> <Th> Calculation </Th> <Th> Span </Th> <Th> Years (approx .) </Th> </Tr> <Tr> <Td> k'in </Td> <Td> 1 day </Td> <Td> 1 day </Td> <Td> </Td> </Tr>

What was the most important god to the maya culture