I am part-time author of books and articles from IT area. Nowadays I am writing my third book. Article take me just a few hours during evening. Books around 250 pages takes ma around one year, written mainly during evenings and nights (my wife is getting insane from this).
In regards to money...no, you can't pay your mortgage from it.
In regards to fun .. yes, it is fun, usually I learn a lot with every book.
In regards to development....yes, it can help me get better job since it is some kind of marketing, and there are not so much candidates with same portfolio. Another thing is that it helps me develop my skills, language and thinking.
In regards how to start ... get in touch with some chief editor, they have a list of topic they and possible readers are interested in. I always send them resume with short description of my previous work and projects.
In regards to money...no, you can't pay your mortgage from it.
In regards to fun .. yes, it is fun, usually I learn a lot with every book.
In regards to development....yes, it can help me get better job since it is some kind of marketing, and there are not so much candidates with same portfolio. Another thing is that it helps me develop my skills, language and thinking.
In regards how to start ... get in touch with some chief editor, they have a list of topic they and possible readers are interested in. I always send them resume with short description of my previous work and projects.