This is not an essay (per the instructions). But it is a wonderful topic to ponder.
There are so many types of writing. Lets look at just a few:
Creative Nonfiction is writing that deals with facts in a non-formal, non-academic style. Memoirs and essays are an example. True stories that use many of the devices of a fictional story, such as a magazine article that is very descriptive of the location and individuals and actions in the event, is another example. Dramatic and unusual events are often the subject of Creative Nonfiction.
Expository writing presents information that has been researched, and provides the idea with evidence and analysis. A conclusion may be part of the presentation. It may present a problem with a solution, or deal with a cause and effect, or compare/contrast ideas or things (or both). It can be written in a very formal way with jargon, fancy vocabulary, citations, and other formal devices, such as academic writing. Or it can be informal, such as a magazine or newspaper or blog article, written for a general audience.
There is technical writing, which is written for a very specific purpose and a specific audience. The little accordion-folded pamphlet that comes with your blender or camera is technical writing. The manual that shows how the airplane engine has been assembled and what each part does is technical writing. If you think about your car, you will come up with most types of technical writing: the procedures required to build the various parts, the descriptions of the various parts and what they do, the procedures required to put all the parts together into a car, the steps for testing the individual parts after they are made and after they are all put together into a car and the procedures to follow if there are any test failures along the way, the manual that comes in your glove compartment about how to operate the car, and the specs that are drawn as fancy graphics that are used in advertising your car.
There is business writing, which is a combination of several types of writing such as grant writing, project proposals and project progress reporting, financial reports for auditors and for shareholders, high-level specifications for product ideas, and advertising writing. There are policies and guidelines. There are agreements with other organizations and companies and governments. These are just a few examples of business writing. Each has its own style and structure.
Creative writing gives delight and dreams. It is stuff that is made up by free imagination based on real life or a life we want or a life we don’t want or a life we never thought of before. There are so many types of creative writing: mysteries, romances, science fiction, dystopian and utopian fiction, poetry, song lyrics, children’s fiction, YA fiction, and I could keep going. A single piece of fiction can come in a set of volumes, a thick book, a paperback, short form, flash form, a single sentence, or anything in between. It is imagination presented in words.
The wonderful thing about being a writer is that you don’t have to pick just one type, and and you don't have to stick to whichever type you picked before you decide to pick another one. Plus, feel perfectly free to create your very own type of writing.