In Emacs, a major definition at the top level in the buffer, such as a function, is called a defun. The name comes from Lisp, but in Emacs we use it for all languages.
|• Left Margin Paren||An open-paren or similar opening delimiter starts a defun if it is at the left margin.|
|• Moving by Defuns||Commands to move over or mark a major definition.|
|• Imenu||Making buffer indexes as menus.|
|• Which Function||Which Function mode shows which function you are in.|