Malaysia Airlines Flight 370 is missing. That much we know. Unfortunately, what we don't know includes where in the world it might be, let alone what happened to it. But the US Navy is in the Indian Ocean right now, trying to help find it. This is what they're doing.
Part of what we know includes the information that the plane could have travelled along one of two arcs, mainly based on data collected from a single satellite out in space. This is what that map looks like, once again: