What is greasing?

greasing in the vehicles is like lotion for moving parts you have this tool that goes over the sockets that are on moving parts like on cam shaft chasis and u joints you squeeze the grease gun and it fills that part with lubricant. When grease starts to come from the sides that's when you stop and you know its fully lubricated sometimes if you did it too much when you whipe it, still might be squeeshing out.