What is the difference between hydrostatic pressure and atmospheric pressure?

Atmospheric pressure is pressure coming from the top from the atmosphere(high elevation,high up in the sky) while hydrostastic pressure comes from liquid with pressure coming from the top from liquids on top(deep sea). So the difference between them is that you get atmospheric pressure from the sky while you get hydrostatic pressure in the sea. So you receive pressure from opposite ends.

True, the standard unit for volume is liters which can be represented by either a lower case "l" or a capital "l"