Blackheads are opposite of pimples. Unlike pimples that appear as a result of inner accumulation of toxins, blackheads appear due to toxins that entered the skin from outside.
This is not a pimple, but an ingrown hair. The hair is trapped inside.
If you your skin came into contact with acid, there will be a reaction on the skin, similar to a pimple. But it is not!
This is a skin reaction of a spider bite, not a pimple. You must immediately go to the hospital.
Herpes appears because of weakened immunity and must not be confused with pimples.
This type of rashes can occur on the skin if you were bitten by a flea.
Scars on the skin because of an injury or a burn can sometimes appear similar to pimples. However, they are not.