What are the major differences between the four gospels?

The four gospels of Mark, Matthew, Luke and John are our primary source for the life of Jesus of Nazareth and are often merged into a singular narrative in the public consciousness. A more careful study reveals that the style, structure and content of these individual books are vastly different and reveal much of the author's own intentions and the concerns of their different time periods.
The gospel of Mark is the shortest gospel and the earliest, giving it a more primitive and urgent feel. Written for a Roman audience, Mark - believed to be a disciple of Peter - aims to present Jesus as a suffering servant. The second gospel, attributed to the apostle Matthew, is more theological, focusing on Jesus as the fulfiller of Old Testament prophecies for a Jewish audience. Luke - whose mastery of the Greek language make many scholars believe he is of the same origin - wrote for gentiles and emphasised the enigmatic phrase 'Son of Man.' By focusing on 'I am' statements and miracles, the fourth gospel (John) is written for all the people of the world and believes Jesus to be the Son of God.