Cool. So even in old days, when Christians were caught in a sin, such as heresy, they buried it an hid it. We have not changed much!
Coptic is a term for a late form of Egyptian written in the Greek alphabet (with some additional characters). It's also a term for the main Christian church in Egypt, which is Monophysite in its theology (rejecting the Council of Chalcedon of A.D. 451, which the Orthodox & Catholic churches accept).
Part of this article is about the earlier discoveries of Gnostic texts at Nag Hammadi. It isn't clear if these newly-found texts are Gnostic or Monophysite in character. There is a big difference: Monophysites are mainstream Christians who differ from other Christians on some points of terminology that most people don't understand anyway, whereas the Gnostics had some notions that were far from the mainstream--some groups wouldn't be considered Christians at all.