If you've ever considered writing, but have been worried about how much money you might need to spend on software before you can even start writing, take heart. Fortunately, it's not necessary to spend any money up front on software to start out writing, as there are quite a few free software programs out there. Having self-published a couple of print books, as well as writing electronic manuals for software I've developed, I thought I'd share what I've found useful.
LibreOffice
LibreOffice is a full blown office productivity suite in the style of Microsoft Office, but completely free. It will run on Windows, Mac, and Linux, which covers most users. For authors, the most useful part of LibreOffice is the word processor, LibreOffice Writer. It offers similar functionality to Word, however it uses older style menus and toolbars rather than the ribbon which has become standard in Microsoft Office. Where LibreOffice Writer excels compared to Word is in its export capabilities.
Word allows you to save as a pdf, but gives you just two quality options. LibreOffice allows you plenty of fine grained control over PDF export, so that you can control many aspects of the pdf generation for quality and features. This is vastly superior to Word, and handy if you need to be able to generate everything from low quality proofs to send via emails to high quality print ready pdfs.
LibreOffice also supports exporting documents as EPUB, which is the most widely supported e-book format.
Of course, you may already have started writing in Word, or maybe Google Docs, but want to give LibreOffice Writer a try. All is not lost, as LibreOffice Writer can open most Word documents just fine. There are actually some things that Word does better than LibreOffice Writer, so instead of picking one or the other, if you already have Word, you can use both, taking advantage of what each does best, and switching between them with your document when you need to.
Scribus
What LibreOffice Writer is to Word, Scribus is to Microsoft Publisher or Adobe Indesign. Scribus is an advanced desktop publishing program, with the ability to accurately create page layouts, and even better control over pdf export than LibreOffice. Scribus doesn't provide particularly strong text editing tools, for example it lacks a spell checker, however as a layout tool it is excellent. The lack of advanced text editing features is not a problem if you edit your text in a word processor like Word or LibreOffice Writer first, and then import it into Scribus for layout.
If you're simply writing textual works like novels, Scribus is definitely not for you, but if you work with highly visual publications like illustrated children's stories or want to publish magazines, and are keen to do the layout yourself, then Scribus is a tool you may want to check out if you don't want to pay up for an Adobe Creative Cloud subscription so that you can use Indesign.
Scribus can take a bit of getting your head around, but it can be worth a look if you want a desktop publishing tool on the cheap. I've self-published two books using Scribus to do all the layout and typesetting, and generate print ready pdfs, and I've been very happy with the results.
Google Docs
Google is most famous for its search engine, but it also makes a cloud based office suite, which includes the Google Docs word processor. A big advantage of a cloud based system like Docs is that you never need to worry about installing any software or backup, as both the software itself and your documents are stored in the cloud, so if anything happens to your computing device, nothing is lost; you just need to log into your Google account again on another device to access your work. Of course it does make sense to ensure you use a secure password for your Google account, as you don't want some evil hacker playing havoc with your hard work.
Apart from cloud storage, one of the great things about Google Docs is the potential for collaboration. If you're wanting someone else to review and edit your work, you can easily share with them, and there's the potential to see in real time changes collaborators make.
Synchronisation is also really great, so if you want to refer to a document on your mobile when you're away from your computer, you can, and when you come back to your computer you'll have the latest changes. With voice recognition on modern smartphones, it's surprisingly easy to add to a document by simply talking to your phone.
Google Docs certainly isn't my choice of software for when it comes to preparing for print, and given it's cloud based nature, it's possible to find you don't have the app active in your web browser, or the document you want to work on downloaded, which isn't an issue you'll have with traditional desktop word processing software.