"Junk DNA" was a term used by atheistic scientists who insist that man has evolved, and thus has lots of DNA that was useful as a lower species but is no longer useful now. The term "junk DNA" referred to an intron or non-coding section of DNA.
In fact, the evolutionists were proven wrong yet again: there is no known "junk DNA." Function(s) of introns are slowly being elucidated. Biologist Jonathan Wells calls Junk DNA an anti-scientific myth that ignores the evidence, impedes research and is based more on theological speculation than good science.