What is the purpose of a title sequence?

The Purpose of a Title Sequence

All films use title sequences to showcase the cast and crew members who where involved in the production. Furthermore title sequences are also used for crediting, this is done so that the main cast members and director are showed of more.

Title sequences are also there to show the production company for example 'Universal Pictures' and 'Paramount Productions' are productions company's that would have produced the film. 

Opening title sequences are vital to a film because they can set the story, the title sequence and opening scene is there to get the audience hooked to the film, but not by spoiling it but buy getting them gripped and wanting to find out more and watch more of the film. A film that does this is 'The Incredible Hulk' film.

The opening sequence sets up the film because it gives a in site to what the film is going to be about, furthermore the scene shows how the main character Bruce Banner played by Edward Norton becomes the Hulk and can maybe suggest from the sequence with the army officer that it will be about that officer come after him and him adapting to being Hulk, which will leave the audience mesmerised and want to watch the rest of the film to see what happens.