Search where in which file the variables were declared?

Question

GNU Emacs 23.1.1

I support someones code. There are many files and directories for headers and source files.

I am wondering if there is an easy way to use emacs, when I highlight the variable name, can I go straight to where it is declared?

Some of the structures in which I work are declared in other header files, and do not go looking for them, I just want to be taken directly.

Thanks so much for any suggestions,

Answer 1

etags, . M-. , .

Answer 2

C-h v RET , *Help*, RET ( ) , .