Check out the fuses or circuit breakers in the breaker box. If there is a main fuse or breaker which has blown or tripped, it will cause the power to be off at all outlets and other connections.
The use of a test light or multimeter is required to check these breakers or fuses. Be sure not to attempt these tests if you are unfamiliar with household electrical devices.
I would change the fuses first if it uses them.
It's hard to tell the problem with so little to go on but I hope this answer helps.
