Sound effect

5 different types of sound effects:

1: Explosion - explosion is a violent shattering or blowing apart of something, for example it can be cause by a bomb. Explosion happens when you want to grab the audiences attention with a certain sound effect for example when and explosion happens in a film or serial, the audience tends to get scared or more intrigued into the film opening sequence. The most common artificial explosives are chemical explosives, usually involving a rapid and violent oxidation reaction that produces large amounts of hot gas. Gunpowder was the first explosive to be discovered and put to use. we have chosen this sound effect because it adds more suspense to the opening sequence and grabs the audiences attention, also it makes the opening sequence stand out. This will be suitable for our film opening sequence as it will be something different from the rest of the films being produced.
https://blog.soundsnap.com/glossary/sound-effects/
2: Isolated sounds - Isolated sounds are the property of blocking off outside sound through use of materials that reduce sound transmission from the exterior environment into the interior environment. isolated sounds are good to use in films because it makes it more suspenseful as some of the sounds or lyrics would be quite (isolated).  Isolated sounds include the sounds of everyday items like doorbells, car horns and telephone rings. These are the real and specific sounds that you hear such as dogs barking, guns firing, doors slamming and car tires screeching during a car chase. We have chosen this as our sound because we want the audience to hear the background noises at some points of the opening sequence instead of the characters talking or music playing in the background, in my opinion I think that this will definitely make our film stand out from the others.
https://en.wikipedia.org/wiki/Sound_effect
3: Foley sounds - Foley sounds are synchronized with the visuals in a motion picture or television program.  This synchronization process is also called audio sound replacement. The magic of Foley places footsteps into a film soundtrack – recreates the rattle of a coffee cup being put down on a table – provides the realistic rustle of clothing and the ever popular punch in the face.  These and many other sounds must be dubbed during post production on the film's soundtrack in order to be heard by the audience. They are named after Jack Foley – a pioneer in the sound replacement field. we have used Foley sounds in our opening sequence because this creates natural sounds that make the opening sequence more accurate and real.
https://www.sound-ideas.com/Page/what-is-foley.aspx
4: Natural sounds:  Natural sounds are sounds that are produced in their actual setting for example nature. They are the sounds of wind, tree branches, animals, insects, cars whizzing by, horns honking, etc., all of which add a layer of realism to your films. Foley is the recreation of noises synced to picture. this is very important as it creates some natural sounds and makes it seem different. we have chosen natural sounds so that it stands out and it makes our opening sequence sound real and calm so that people enjoy it, for example when the stalker and the victim go through the quite, dark corridor, there are no sound effects used there but they only thing that can be heard is the wind whistling and the doors opening and closing, this is where the natural sounds are being present.
https://en.wikipedia.org/wiki/Sound_effect
5: Diegetic & non diegetic sounds: Diegetic sounds arise from the subjects or objects that appear on screen, or are implied to be present within your film’s world. These can be the actors’ voices, sounds of footsteps, or a tinkling piano, on the other hand Non-diegetic sounds are the tones emitted from subjects or objects that do not appear on screen, nor have they been implied to be present within your film’s world. A voice-over or a soundtrack (where the music is not being performed within the film) are solid examples of this. we have chosen this type of sound to make it sound different and unique from the other opening sequences.
http://www.elementsofcinema.com/sound/non-diegetic/
http://filmsound.org/terminology/diegetic.htm