What are the distributions of red hat linux?

Yes.

Red hat is just the distribution. The Linux project determines the current revisions and allows people to charge for distributions just in case you don't want to load everything by hand.

an operating system developed by red hat inc.

There is no longer a product known as "Red Hat Linux." All versions of Red Hat are made for enterprises. At one time, there was a consumer version, but it has since been discontinued, in favour of...

1994