The Catholic Bible contains more books than Protestant translations. Why?
The Books of the Bible were written as individual books or writings. Over the course of thousands of years, not everyone has agreed upon which books are inspired. When the Reformation came along, Martin Luther translated the Palestinian Canon, which leaders of the Reformation have followed since. The Church has authoritatively defined the canon following the Greek (Alexandrian) Canon, which includes the books now contained in the Catholic translations of the Bible. The differences between Protestant translations and Catholic translations of the Bible are in the Old Testament or Hebrew Scriptures. Today many Protestant translations of the Bible contain the additional Catholic books, calling them by the name of Apocrypha. Catholic scholars use the term deutero-canonical for these books unique to the canon used by Catholics and Orthodox.