I did not write this, but it sums up everything I believe.
The Catholic Bible has 7 more books than the Protestant Bible.
The apocrypha consists of a set of books written between approximately 400 B.C. and the time of Christ. The word “apocrypha” (απόκρυφα) means “Hidden.” These books consist of 1 and 2 Esdras, Tobit, Judith, the Rest of Esther, the Wisdom of Solomon, Sirach, (also titled Ecclesiasticus), Baruch, The Letter of Jeremiah, Song of the Three Young Men, Susanna, Bel and the Dragon, The Additions to Daniel, The Prayer of Manasseh, and 1 and 2 Maccabees.
The Protestant Church rejects the apocrypha as being inspired, as do the Jews, but in 1546 the Roman Catholic Church officially declared some of the apocryphal books to belong to the canon of scripture. These are Tobit, Judith, 1 and 2 Maccabees, Wisdom of Solomon, Sirach (also known as Ecclesiasticus), and Baruch. The apocryphal books are written in Greek, not Hebrew (except for Ecclesiasticus, 1 Maccabees, a part of Judith, and Tobit), and contain some useful historical information.
THE REASON FOR THE DIFFERENCE:
- Neither Jesus nor the apostles ever quoted from the Apocrypha. (I read the website link that Abu provided which talks about this, and the irony is that the article explaining the error of a “myth”, is actually full of error. All of the quotes that the author used were not direct. They were simply passages with similar meanings to the ones that Jesus and the apostles used. You cannot say that just because the passage has a similar meaning, that it is directly quoted. Also, it says that Jesus and the apostles observed Hanukkah, which is only found in the apocrypha, which means the apocrypha has to be in the Bible. What? It was a VERY common Jewish tradition. Observing it has no correlation between whether it should be in the Bible or not.
- Jesus referenced the Jewish Old Testament canon from the beginning to the end and did not include the apocryphal in his reference.
- Jerome (340-420) who translated the Latin Vulgate which is used by the RC church, rejected the Apocrypha since he believed that the Jews recognized and established the proper canon of the Old Testament.
That is why the protestants didn’t include it. Good writings, but not inspired by God for Scripture. Hope that helps. Some Catholics show quotes of the apostles that are similar to verses from the Apocrypha, but there are no direct, word-for-word quotes from the Apocrypha anywhere in the Bible.
Also, a Catholic mentioned on Yahoo Answers (I’ve been browsing around to find out the reason for the removal of the Apocrypha) that Luther dropped the books because of his selfish thinking that “You may only get to heaven through the Means of Grace.” I do not know why Catholics don’t believe this, as it is VERY CLEARLY stated in Ephesians 2: 8-9 “For it is by grace you have been saved, through faith —and this is not from yourselves, it is the gift of God— 9 not by works, so that no one can boast.” Catholics teach that good works will get you in to heaven. Sorry, but unless you think Paul is a liar, you’re wrong

Additional reference, Romans 3:28 “For we maintain that a person is justified by faith apart from the works of the law.”
It is my personal belief that the Catholic leaders made the teaching of Salvation through goodworks so that people would try to do more good works, and make society a bit better

(and the Catholic church also has been known to start certain traditions (lies) for its own benefits, such as the selling of indulgences purely for money, even though they have no Biblical origin, and are a lie. Also, if purgatory is real, why does no Biblical figure talk about it? Jesus and the Apostles never say purgatory exists, nor do they ever mention it (and I think they would’ve if it did exist, because purgatory is not a minor belief).
Now you may say, “But the Apocrypha teaches that we are saved through good works and faith.” Well, that may be, but the Apocrypha is not accepted by all, while the New Testament is, and the New Testament says that the Apocrypha (atleast the part about good works) is wrong.