Okay, something I need to get off my chest. As a result, I'm making a cut so you don't have to deal with text flood.
Now, LibreOffice (and by extension OpenOffice) isn't that bad of an application. Sure, on Windows, the kerning for most fonts is so horrible it could cause brain damage in the minds of any decent designer, but it does what's needed. It's a word processor, based loosely on the old MS Office Word/MS Works Write UI, with all the features up could need for editing and creating documents. And if you want good typesetting, use LaTeX. It's better suited for the role.
That said, something I see when people talk about not being able to afford Office for the desktop is a reaction of "Just use LibreOffice." This would be a good suggestion, if not for how quick people are to jump on that suggestion.
LibreOffice is good for most people who are used to word processors. But it's not for everyone. In fact, it can be outright overkill for some people.
If someone just needs something to write in rich text (bold, italics, etc) without worrying about a lot of options, Windows comes with WordPad built-in, and saves to the RTF (Rich Text File) format. macOS likewise comes with TextEdit, which is both a text editor and a rich text editor like WordPad. There's quite a few options that use RTF as well, such as Jarte. Oh! And it's also the preferred format of files for my favorite writing tool on Windows and macOS, Scrivener!
On Linux, you can also choose Abiword or Calligra Office's word processor, which are both quite nice.
If you have a newer Mac, Apple's Pages is free on the App Store, and is probably my favorite word processor out there. And for older macs running newer macOS versions, the app is only $20 as a one-time fee. I'm admittedly jealous that there's not a Windows version available...kinda.
See, there are also the online-centric options as well. Word Online is a simplified version of Word 2016, and is completely free for anyone using a Microsoft account with OneDrive. Likewise, Google Docs is free, and has a much more simplified UI than desktop apps, but you have to store everything on Google Drive, since the document isn't an actual file that's synced. There's also Apple's iCloud, with Pages being free there as well, and fairly close to the desktop app on macOS, but relies on Apple's iCloud for file storage.
Additionally, none of the online options offer an Offline mode with the exception of Google Docs, though that's only if you use Google's own Chrome browser. Which is a shame, but what can you do?
All in all, there's plenty of cheap or free options aside from LibreOffice. Feel free to look around, and remember that if you really want Word for desktop, an Office365 account is only $6.99/mo or $69.99/yr as a subscription for 1 install at a time ($9.99/mo or $99.99/yr for up to 5 installs at once). Office 2016 Home and Student (which includes Word 2016) is only $149.99, but only allows for one PC (or Mac) install for that license.