What is the purpose of a title sequence and film opening? What makes a good film opening? (Safi)

The purpose of these are to bring in the audeince into watching the film. Everything matters. From the music to the small graphics. The music could bring an array of emotions depending on the film, for example if it's a scary film the music should be ominous to add that suspence and fear.The graphics can add that extra wow to pull the audience in, even the typography matters, again usuing the example of a scary film, the graphics should make the place possibly darker, create an eerie fog, make the scene look a bit more decrepit and the typography could look like the letters have blood dripping from them or something like that. The lighting is also key, this time using the example of a happy film, the lighting should be very light to set the mood if too dark it could mean something is amiss. The colours and textures that are used are also important, again using a happy film as an example, the colours should be bright and vibrant, full of life as they say, such as yellow, pink, light blue, pastel kind of colours.