The following genres are listed and explained in alphabetical order. What are genres? Well, just like in music, they are categories. In this case, they are categories of writing where the audiences can vary as well as the content and structure. Think of techno or rap or pop music; the content of all of those music genres is different than country music, yes? But it’s all under the umbrella of music.
And yes, there is sometimes overlap between writing genres just like there is with musical genres.