Two books of the Old Testament - Wisdom and II Machabees - were written in Greek. The rest of the Old Testament was written in the Hebrew language. The New Testament was written in Greek, with the exception of St. Matthew's Gospel which - according to the unanimous testimony of Christian antiquity - was written in Hebrew or Aramaic.

The books of the Bible were very likely written in the cursive style of writing. The cursive (or "running hand") style joins the letters of a word together as when we write today. In addition, the ancients had two other styles of writing: the lapidary (from the Latin word, lapis, meaning stone) and the uncial (from the Latin word uncia, meaning inch). The lapidary style was followed in inscriptions on stone monuments and used only capital letters. The uncial style was used in fine editions of books and in elaborate Bibles and employed large disconnected letters resembling the capitals. In "uncial" writing there were no spaces between the words or sentences and punctuation marks were used rarely. The word "uncial" comes from St. Jerome's description of some Bibles of his time as being written in "letters an inch high."

Material taken from http://www.cathtruth.com/catholicbible/bookbook.htm