According to Wiki a cheescake is a form of pie, so that means it is a cake.
@Grey, the second picture down in may last post is a pumpkin "pie" which in my view is in fact a tart.
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If we are to go to Wiki again then it kind of contradicts itself, as a tart is in fact a type of pie....in fact there seem to be three types of pie,
1 is a lidded pie, which is some sort of filling in a dish, and with a (usually pastry) lid on top... e.g. pot pie.
2 is an open pie, which is what I call a tart, and will have pastry base and edge, which is then filled with whatever you want.
3 is a (proper) pie, which would have the filling totally encased like a cross between a tart and pot pie.
Even by those definitions a cheescake is not a pie because it is not made in the same way, the tart/open pie thing has sides to hold in what is inside, wheras a cheescake is made from layers like any other cake (biscuit base + cream cheese stuff + whatever goes on top)
So there we go, a cheescake is not a pie because it has no sides nor a lid
