If you're talking about which books are in the Bible, note that the Catholic and Protestant Churches use the same books for the New Testament.

The Catholic Church (and the Orthodox, except for the Ethiopian Orithodox) uses the Septuagint canon for the list of old testament books--this was Greek language bible in circulation at the time of Christ and which was known to the Apostles. The Septuagint had been current and had been accepted and used by Jews for about three centuries before the time when the books of the New Testament were written. The authors of the New Testament wrote in Greek, and overwhelmingly seem to have used the Septuagint for their quotations form the Old Testament, and the early Church used the Septuagint as their Old Testament.

At much the same time as the Septuagint was being produced (i.e., 3rd c. BC), other translations or summaries of the Scripture books were being made into Aramaic, the language of Jews living in Palestine and the Near East: these are called the “Targums”, from a word meaning "translation", and were used to help Jewish congregations understand their scriptures. Many Targums are not so much translations as paraphrases and interpretations, with comments. This is helpful when we come across an obscure passage to see what those closer in time to the original writing interpreted it. In time, rules of exegesis were determined, the translations were fixed in writing, and were thus widely circulated even before the time of Christ. No extant Targums contain all the books of the bible, so they are more useful for biblical interpretation but not so much when considering the question of setting the canon.

Jews began to abandon the use of the Septuagint around the 2nd c. AD, most importantly because that those Jews who did not want to convert to Christianity wanted to put some distance between themselves and the new Christian religion which was using it. Even Greek-speaking Jews started to use other, newer, Greek translations. This "Masoretic Text" of the Jewish Bible was fixed from that point onwards--it contained fewer books than the Septuagint version:

• It omits the following books: Tobit, Judith, 1 & 2 Maccabees, Wisdom, Sirach, and Baruch

• It removes material from the following books: Esther, Daniel, Baruch

The early Protestants chose to use the Masoretic text for a variety of reasons, to put some distance between themselves and the Catholics. In particular, since 2 Maccabees discusses praying for the dead and Protestants don't want to do that, it's convenient that the Masoretic text omits that book.

There's lots of interesting material online about the old bible texts that were found amongst the Dead Sea Scrolls. There are 235 biblical texts included in the Dead Sea Scroll documents. Digital photos of some scrolls and fragments are available online in a number of places. Two are:

• http://dss.collections.imj.org.il
• https://www.deadseascrolls.org.il

The Dead Sea Scrolls were surrounded by a bit of sensationalism when they were first discovered, as well as a lot of academic staking of turf which slowed their publication. One still reads of National Enquirer-level absurdities about “secrets” supposedly contained in them.

The identified texts fall into three general groups:

• About 40% are copies of books which are found both the canon of the modern Jewish Hebrew Scriptures and the Septuagint.
• Approximately another 30% are texts which are not in the modern Jewish Hebrew canon, but which are either in the Septuagint canon (e.g. Book of Tobit, the Wisdom of Sirach), or which are are in the Beta Israel (Ethiopian Jewish) canon (e.g. the Book of Enoch, the Book of Jubilees, Psalms 152–155). These do not appear in modern Protestant or Catholic (or other Orthodox) bibles. There are also important early commentaries (“Targums” and “Peshers”) on several biblical texts.
• The remainder (roughly 30%) are manuscripts of previously unknown documents that shed light on the rules and beliefs of a particular group or groups within greater Judaism, most likely the Essenes

We have other manuscripts e.g. the "Nash papyrus" and the "Hexapla" as well as the "Peschitta" and many others. An internet search with just those three terms will turn up a ton of material on early biblical manuscripts.

It's a fascinating subject.

If you're talking about which books are in the Bible, note that the Catholic and Protestant Churches use the same books for the New Testament.

The Catholic Church (and the Orthodox, except for the Ethiopian Orithodox) uses the Septuagint canon for the list of old testament books--this was Greek language bible in circulation at the time of Christ and which was known to the Apostles. The Septuagint had been current and had been accepted and used by Jews for about three centuries before the time when the books of the New Testament were written. The authors of the New Testament wrote in Greek, and overwhelmingly seem to have used the Septuagint for their quotations form the Old Testament, and the early Church used the Septuagint as their Old Testament.

At much the same time as the Septuagint was being produced (i.e., 3rd c. BC), other translations or summaries of the Scripture books were being made into Aramaic, the language of Jews living in Palestine and the Near East: these are called the “Targums”, from a word meaning "translation", and were used to help Jewish congregations understand their scriptures. Many Targums are not so much translations as paraphrases and interpretations, with comments. This is helpful when we come across an obscure passage to see what those closer in time to the original writing interpreted it. In time, rules of exegesis were determined, the translations were fixed in writing, and were thus widely circulated even before the time of Christ. No extant Targums contain all the books of the bible, so they are more useful for biblical interpretation but not so much when considering the question of setting the canon.

Jews began to abandon the use of the Septuagint around the 2nd c. AD, most importantly because that those Jews who did not want to convert to Christianity wanted to put some distance between themselves and the new Christian religion which was using it. Even Greek-speaking Jews started to use other, newer, Greek translations. This "Masoretic Text" of the Jewish Bible was fixed from that point onwards--it contained fewer books than the Septuagint version:

• It omits the following books: Tobit, Judith, 1 & 2 Maccabees, Wisdom, Sirach, and Baruch

• It removes material from the following books: Esther, Daniel, Baruch

The early Protestants chose to use the Masoretic text for a variety of reasons, to put some distance between themselves and the Catholics. In particular, since 2 Maccabees discusses praying for the dead and Protestants don't want to do that, it's convenient that the Masoretic text omits that book.

There's lots of interesting material online about the old bible texts that were found amongst the Dead Sea Scrolls. There are 235 biblical texts included in the Dead Sea Scroll documents. Digital photos of some scrolls and fragments are available online in a number of places. Two are:

• http://dss.collections.imj.org.il
• https://www.deadseascrolls.org.il The Dead Sea Scrolls were surrounded by a bit of sensationalism when they were first discovered, as well as a lot of academic staking of turf which slowed their publication. One still reads of National Enquirer-level absurdities about “secrets” supposedly contained in them.

The identified texts fall into three general groups:

• About 40% are copies of books which are found both the canon of the modern Jewish Hebrew Scriptures and the Septuagint.
• Approximately another 30% are texts which are not in the modern Jewish Hebrew canon, but which are either in the Septuagint canon (e.g. Book of Tobit, the Wisdom of Sirach), or which are are in the Beta Israel (Ethiopian Jewish) canon (e.g. the Book of Enoch, the Book of Jubilees, Psalms 152–155). These do not appear in modern Protestant or Catholic (or other Orthodox) bibles. There are also important early commentaries (“Targums” and “Peshers”) on several biblical texts.
• The remainder (roughly 30%) are manuscripts of previously unknown documents that shed light on the rules and beliefs of a particular group or groups within greater Judaism, most likely the Essenes

We have other manuscripts e.g. the "Nash papyrus" and the "Hexapla" as well as the "Peschitta" and many others. An internet search with just those three terms will turn up a ton of material on early biblical manuscripts.

It's a fascinating subject.

If you're talking about which books are in the Bible, note that the Catholic and Protestant Churches use the same books for the New Testament.

The Catholic Church (and the Orthodox, except for the Ethiopian Orithodox) uses the Septuagint canon for the list of old testament books--this was Greek language bible in circulation at the time of Christ and which was known to the Apostles. The Septuagint had been current and had been accepted and used by Jews for about three centuries before the time when the books of the New Testament were written. The authors of the New Testament wrote in Greek, and overwhelmingly seem to have used the Septuagint for their quotations form the Old Testament, and the early Church used the Septuagint as their Old Testament.

At much the same time as the Septuagint was being produced (i.e., 3rd c. BC), other translations or summaries of the Scripture books were being made into Aramaic, the language of Jews living in Palestine and the Near East: these are called the “Targums”, from a word meaning "translation", and were used to help Jewish congregations understand their scriptures. Many Targums are not so much translations as paraphrases and interpretations, with comments. This is helpful when we come across an obscure passage to see what those closer in time to the original writing interpreted it. In time, rules of exegesis were determined, the translations were fixed in writing, and were thus widely circulated even before the time of Christ. No extant Targums contain all the books of the bible, so they are more useful for biblical interpretation but not so much when considering the question of setting the canon.

Jews began to abandon the use of the Septuagint around the 2nd c. AD, most importantly because that those Jews who did not want to convert to Christianity wanted to put some distance between themselves and the new Christian religion which was using it. Even Greek-speaking Jews started to use other, newer, Greek translations. This "Masoretic Text" of the Jewish Bible was fixed from that point onwards--it contained fewer books than the Septuagint version:

• It omits the following books: Tobit, Judith, 1 & 2 Maccabees, Wisdom, Sirach, and Baruch

• It removes material from the following books: Esther, Daniel, Baruch

The early Protestants chose to use the Masoretic text for a variety of reasons, to put some distance between themselves and the Catholics. In particular, since 2 Maccabees discusses praying for the dead and Protestants don't want to do that, it's convenient that the Masoretic text omits that book.