Some of the letters in the New Testament are called the 'catholic epistles'. Catholic in this sense (as in the Apostles' Creed) refers to being universal in nature. The seven letters that make up the catholic epistles are:
The gospels can be divided into two types. Matthew, Mark and Luke are 'synoptic' meaning they give a synopsis of the life of Jesus Christ. They agree in most passages about the various events in the life of Christ. In fact it is easy to see a harmony amongst these books. There are however some differences which are interesting to study. The gospel of John on the other hand is arranged not chronologically, but in the order of ascending importance of signs and works by Jesus. In general, the gospels were written to different audiences, that is sometimes Jewish, some Greek, etc.. and the authors specifically emphasized areas of the gospel of interest to the audience.
There are 27 books in the New Testament. To find a specific book, some of the following tips may help:
Then, the 'T' books are all together: I and II Thess...I and II Timothy...and Titus.
After this you'll just have to remember the order of the books, except that
Revelation is of course the last book in the Bible and the letters of John are right
before it (except for Jude).
Another interesting memory aid to note, is that all the books that start with the letter 'T' are in alphabetical order within the NT. That is Thessalonians, then Timothy, then Titus. The same is true for 'J' - James, then John (after Peter) before Jude.