ASCII File, Known as Text File, in Fact A Binary FIle

ASCII just an encoding that "maps" the binary code (8 bits at a tile, only uses 7 bits actually) to a human readable character.

http://www.cs.umd.edu/class/sum2003/cmsc311/Notes/BitOp/asciiBin.html
http://www.delorie.com/gnu/docs/emacs/emacs_464.html