Dumb Mac question

So … is there a basic writing program that comes with a Mac? It seems to come with a whole wack of stuff, like iPhoto, and contacts and some sort of AppleScript Editor … but is there like a Microsoft Word Document type thing? ( obs not Microsoft …)

And/or, what is a program that is free/cheap that is easily shared between Mac and HP users? I want to be able to send stuff for beta without having to import/export it as something else.

If it exists here, I'm not seeing it.

Thanks in advance.