How to edit binary file on Unix systems [closed]

In vim You can type :%!xxd to turn it into a hexeditor. :%!xxd -r to go back to normal mode. xxd is shipped in a vim installation.

See here for some remarks about editing binary files with vim (boils down to :set binary to avoid trouble, use only the "R" or "r" command to change text, don't delete characters).

If You are an Emacs fan, see here for a guide on how to edit a binary file with Emacs.

You can also try ghex2 GNOME utilities. This give you the automated hex-to-ASCII on the side, as well as the various character/integer decodes at the bottom.
_{(source: googlepages.com)}