The gravito-electro-magneto-strong-weak force is the concept that gravitational, electromagnetic, strong and weak nuclear forces can be unified as one force at high enough temperatures (temperatures is another way of saying energy).
The strong interaction is a very strong force, however it is short-ranged. It is responsible for holding the nuclei of atoms together. It is 10^(41) times stronger than gravity.
The electromagnetic force causes electric and magnetic effects and allows particles which have an electric charge to experience electrostatic repulsion. It is also a long ranged force. It is 10^(39) times stronger than gravity.
The weak force is responsible for radioactive decay and neutrino interactions and is a short range force. It is 10^(28) times stronger than gravity.
The gravitational force is weakest out of the four fundamental forces, but is long ranged like the electromagnetic force. It is believed that the source of gravity is the geometry of spacetime itself, that which deals with curvature.
Electromagnetism and weak nuclear forces are unified at around 10^(15)K. At increasing temperatures, it is believed the strong force will also unify with this, and in even more incredible temperatures, gravity also. Some unified theories predicts gravity falling from the other three forces at around 10^(27)K.