The intertestamental period is the Protestant term and deuterocanonical period is the Catholic and Orthodox Christian term for the gap of time between the period covered by the Hebrew Bible and the period covered by the Christian New Testament. Traditionally, it is considered to cover roughly four hundred years, spanning the ministry of Malachi (c. 420 BC) to the appearance of John the Baptist in the early 1st century AD, almost the same period as the Second Temple period (530 BC to 70 AD).
It is known by members of the Protestant community as the "400 Silent Years" because it is believed to have been a span where God revealed nothing new to his people.
It is said that many of the Deuterocanonical or Anagignoskomena books, accepted as scripture by Roman Catholicism and Eastern Orthodoxy respectively, were written during this time. This is also the time when many pseudepigraphal works were produced. An understanding of the events of the intertestamental period provides context for the New Testament.