So I found out the other day that I have a pet peeve.
A scar is a far different from a scratch. Scars are old or healed perminant damage to skin. Some times they hurt but most of the time not so much. To get scars a wound needs to be fairly deep or the damage needs to last for a long time. Basically to get a scar you usually suffer a grecious wound first. A scratch is a shallow surfave wound, they itch and burn a little... You rub disinfectant on it and forget about them. A scratch has to have happene recently, basically they are pretty fresh wounds but nothing to worry about.
As an artist with small scars covering my hands and legs from creating sculptures, people mixing scars and scratches up irks me... Also it can change the context of a sentence. A man with scars covering the left side of his face and down his left arm is a verry different mental image to a man with scratches on his face and arm.
Well nice to get that out there. I won't ever abuse someone about making this mistake because English is a really silly language, but it will usually make my eye twitch.