Hoodies.

hoody |ˈhʊdi| (also hoodie)

noun (pl.hoodies)

a hooded sweatshirt, jacket, or other top. 

Some have zippers, some don't. Some have designs and cloth patterns while others are plain. 

Personally, I love hoodies. They're comfortable and cosy. They can be large and oversized, or fitting and slim. 

Many love them.

Why?

Hoodies can give you comfort. They give you protection. They give you warmth. They help express what you feel.

When you're feeling like shit and there's guests in the house, you wear a hoodie with your head covered so you don't have to talk to people, or let them see your face. You want to be alone. 

I read in an article, I quote: "Kids in hiding, afraid of being seen, and at the same time embodying in their everyday uniform the furtive tunnel-vision that seems to define their bleak, introspective vision of the world outlook. Perhaps that's the real meaning of the hoodie."

Conclusion: 

Oversized hoodies are basically hugs.

I may not need to be cold to wear it, just in need of comfort.