Is pimple caused from bacteria? if that is true then how do we prevent bacteria to get in the skin? lately i have been getting pimples, why?

Pustule: If you're referring to a pustule(which does contain a small amount of pus), it is a bacterial infection usually caused by the staphylococcus bacterium which frequently colonizes our skin. If one has frequent staph skin infections like boils due to invasion of these bacteria, a course of antistaph antibiotics is often required to eradicate the colonies of staph from the skin,but not for just pimple