When you read science fiction, some books uses quantum entanglement as a form of instantaneous communication. This isn't how quantum entanglement works. You can learn information about an electron lightyears away right as it happens, but it can't be used for communication.
There are two differnt spins an electron can have: up or down. Before you measure which spin it has, it has both simultaneously. Once you measure the spin, it breaks it down to one spin. If the electron is entangled with another, then as soon as the spin of one is measured, the other has the same spin. It can't be used for communication though, for you can't tell if it's one spin or both simultaneously.