5.4 What about "sid"?
sid or unstable is the place where most of the packages are
initially uploaded. It will never be released directly, because packages which
are to be released will first have to be included in testing, in order
to be released in stable later on. sid contains packages for both
released and unreleased architectures.
The name "sid" also comes from the "Toy Story" animated
motion picture: Sid was the boy next door who destroyed toys :-)