why donuts be always in round shape not in other shapes?

I think it is probably easier to make them that way, and also to pack them. But I don't know for sure, I am really just guessing here!

It has been that way ever since, and if you change their shape, people may not like it. Donuts have always been round, it's like their signature shape, their mark. Also, because in that way, it would be easier to pack them.

Believe it or not! It is science to blame. Any fluid settles down to a circular shape when no force except gravity is acting on them. So when dough of a Donut is patted down it assumes the shape of a disk. The hole is made after wards by intentional human intervention. The hole is again science in action. This gives the Donut more area to bake/fry uniformly and so the core of the donut is not unbaked, raw dough. The same is in the case if a Vada or a Chekodi, savories, form South India. Uggani - Bajji, from your region is an entirely different!

on my knowledge,donuts or dough knots, came to different shape like ballstype,straight,twist etc..it is popularized by americans(others believe that it originated in germanic countries because their cookies and cake has a hole in the center but american disagree to that)..in 1847 mason crokett gregory(from maine)invented the donuts(others believed that he is a sea captain and brought the idea in america)..he hated donuts that everytime he cooked it,it is always uncooked in the center..so his solution is:make a hole on a round dough so the donut will cooked evenly..and now it is known that donuts have a hole in the center if it doesnt has a hole it is not donuts.(hope it helps..sorry for my grammar)