Horizontal datums are used for describing a point on the earth 's surface, in latitude and longitude or another coordinate system. Vertical datums measure elevations or depths. In engineering and drafting, a datum is a reference point, surface, or axis on an object against which measurements are made.orizontal datums are used for describing a point on the earth 's surface, in latitude and longitude or another coordinate system. Vertical datums measure elevations or depths. In engineering and drafting, a datum is a reference point, surface, or axis on an object against which measurements are made.
There are 25 known species of pythons in the world. Like all snakes, pythons are cold blooded. Pythons are not venomous; they kill their prey by constriction. Some of the different types of pythons are the reticulated python, the ball python, the Burmese python, the green tree python, and the carpet python. While some of these species should not be held captive by a non-professional, other types of pythons can make good pets.
Rat snakes are one of the largest kinds of species of snakes, with over 50 types of sub-species. One of the more common kinds of sub-species is the yellow rate snake. The yellow rate snake can reach up to ten feet but, in general, will grow as big as five to seven feet. These snakes are nonvenomous; however, there have been cases where some yellow rates snakes have been found to contain small doses of venom.