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Just off the western coast of Africa is where you'll find Null Island, or at least the place where it should theoretically be. At the precise location, you'll find little more than open water, but many computers seem to have a different impression. That there are all kinds of people who visit there, taking pictures, tweeting, and doing all sorts of normal 21st century things.
The discrepancy, as Minute Earth explains, is all due to how computers differentiate between two different but similar things: the number 0, and the absence of a value at all. Or more particularly, how they sometimes mix them up.
Mistaking null for zero is far from the only trouble that null can cause. Another recurring problem arises for poor folks who have the last name "Null." It's easy to understand as a human, but can form an inherent contradiction for computers, one that can make many normal scenarios a nightmare for people who have that name. At least they have their own non-existent island.
Source: Minute Earth
