What is the purpose of a 'sweat shirt'?

I neve rreally worke dit out...is it to make you sweat...or absorb sweat?

 

Why would you buy and/or wear a garment that specifically promised to make you sweaty?

 

I'd return my PVC gimp suit if it didn't make me sweaty.

 

so it's supposed to not make you sweaty...ok...why does mine make me sweat then?

 

It only makes you sweat if you wear it. Leave it at home and you'll sweat less.

Sweat shirts are one of those things invented to be sold, not to be worn.

 

I think they're called sweat shirts because they're made in overseas sweatshops.

 

Isn't it linked to the term 'sweater'? The new garment being a combination of shirt and sweater?