I've been writing fiction since I was sixteen. In those early days, I wrote by hand, mostly in A4 notebooks. The first attempt at novel writing was a sequel to H.G Wells's The Time Machine. I imagine like many who've read it, Weena's fate was fictionally unacceptable and something had to be done about that. I no longer have this nascent piece of work, but it was amateurish.
Then I discovered the work of Jack Vance and went merrily on a path of aping his style, which is dangerous to do. These sorties into novel writing were also longhand.
I no longer own any of them.
I got serious with computing in the early 90s and began writing with word processors, firstly with AmiPro, as my workplace was Lotus-oriented, then I migrated to Microsoft Word, and finally LibreOffice.
I still have all of the stories I've written on word processors.
In recent years I've toyed with two different writing programs, both free. The first is yWriter. This is a Windows only app (though it can run under Linux using Mono) written by a gentleman by name of Simon Haynes, who is perhaps better known for his Hal Spacejock series of SF comedy novels.
I don't have this installed on any computer, so no screenshots, but it works by getting you to write in scenes. Scenes can be thought of as "sub-chapters" although it's perfectly fine if scenes and chapters are coterminous. The rationale behind this is that your novel becomes easier to manage, rather than rifling through a 300 page LibreOffice document looking to see if Bob really did put $100 on a horse on page 45 or not. By subdividing into scenes, chapters and then the novel itself can be built up.
Apart from writing scenes, there's components for you to add characters, location, items and so forth. So, you could add "$100 bet" as an item, and add that to the scene where Bob put his money down. Additionally, you could add "the local" as a location, and do the same thing. It's all about cross-referencing, and, in theory, making the creative process more structured.
For a free application, yWriter is extremely full-featured.
Then we have Manuskript.
It's essentially the same thing as yWriter, except it's open source and multi-platform. It also operates under the same scene-level paradigm.
It's not as polished or as featured as yWriter, and it's lacking a little in documentation. It's also a bit confusing to use, as its layout is not as intuitive.
My problem as a writer with these applications is simple: they're fiddly. I understand that subdividing your work into cross-referenced scenes, complete with references such as locations, characters, items etc, would make things purpotedly easier for certain kinds of writers. And people have commented positively on them. Me, I can't write in scenes. I'm old-fashioned. I start at "once upon a time" and conclude with "the end". I don't start at page 300, write to the end, and write the beginning like so many guides advise you to do.
Another thing is firstly learning the software, and then adding entries to character, location, et al. I'm sorry, but that sounds like hard work, when I could be simply writing the story in question. I get that yWriter and Manuskript et al would make life easier for folks who struggle with continuity (i.e Bob and his bet) or who do like to write in discontinuous fragments. To me, it's all fussy. I guess what I'm saying, is that I like the idea of writing software, but I've found navigating through them, learning their quirks and features, and playing data entry clerk to be non-productive, anti-creative, and dare I say it, not fun.
So there it is. My brief expatiation on writing software. Note that I haven't even tried stuff like Scrivener, Story Mill etc, but I imagine their basic paradigms wouldn't be that much different. I'll stick to writing A-Z in a word processor, thanks.