Why should structure names have a typedef?

It is an odd quirk in the C language, structure tag names are stored in a different namespace (symbol table). The C++ language got rid of this behavior. The typedef creates an alias for the structure type in the global namespace. So you don't have to type "struct" before the structure name.

Not sure what Ritchie was smoking when he defined this behavior. I'm guessing at some kind of problem with the parser in an early version of the compiler.