According to the online edition of Merriam-Webster Dictionary, genre is defined as:
a category of artistic, musical, or literary composition characterized by a particular style, form, or content.
I think a difficult thing for writers when they start out is to determine what genre they are writing. It seems like an easy question, but I can tell from my own experience that one needs to put thought into it.
When I decided that all those characters that continued to show up in my head needed to go someplace else, I started writing their stories. I knew I wasn't writing romance because there wasn't any hot romantic scenes. I was confused if I was writing women's fiction or literary fiction geared toward women since my stories were character-driven rather than story driven. In the end, I figured out I was writing women's fiction and queried agents who represented that genre.
But a funny thing happened after securing representation - my agent told me to write something new in a different genre. It wasn't very hard for me to decide on middle grade (it helps have two young sons), although I did try my hand at YA for one manuscript (I quickly learned I didn't know how a YA character spoke or acted). I feel like I've found my voice - although some of those women's fiction characters tend to show up now and then and I have to tell them "later".
Have you ever switched genres or do you write in multiple genres?