Speedbar is an Emacs Lisp program which allows you to create a special
skinny frame with a specialized directory listing in it. This listing
will have both directories and filtered files in it. You can then load
files into your emacs frame, or expand the files to display all the
tags that are in them and jump to those tags. You can also expand
multiple directories into your speedbar frame.

Using Shift with the mouse is considered a "power click" which will
ignore any cached data that might be related to the navigation
desired. When loading a file, a power click will pull that file into a
new frame.

For PC users with two button mice, a button1 double click acts as the
mouse-2 click most emacs users are familiar with.

Additional keyboard commands are available for friendly file IO
functions such as Rename/Copy/Delete, Loading lisp files, and
compiling lisp files.

Speedbar is more than just file browsing, however. Speedbar is a
generalized browser. Speedbar supports:

* multiple tagging methods for files (such as etags, imenu, and
  semantic)

* multiple major display modes (such as buffer lists, project lists,
  and EIEIO class browsing,)

* multiple minor display modes that appear when you view special
  files, such as Info pages, or read mail with RMAIL.