There are many shapes of bacterias. Some bacterias classified by basic shapes :
Cocci.
Cocci bacterias are oval, round. They can be seen as chains.
Bacilli.
Bacilli bacterias' shape is like sticks. They are long and rather thin.
Spiral bacterias.
These kind of bacterias are curved.
There are three kind of spiral bacterias,
Vibrio : Looks like the shape of a comma.
Spirilla and Spirochetes.
Some other bacteria shapes are star shaped bacteria and rectangular bacterias.