Antibiotics are medications used to treat bacterial infections. They work by targeting specific mechanisms in bacterial cells, like their cell wall formation or protein synthesis.

The bacterial types you mentioned (coccus, bacillus, and spirillum) refer to different bacterial shapes:

* Coccus: Round or spherical

* Bacillus: Rod-shaped

* Spirillum: Spiral or corkscrew-shaped

Antibiotics can target bacteria of various shapes, depending on the specific antibiotic and the type of bacteria causing the infection.