If you've ever used Mac OS X, you'll know that it has always had the facility to create a PDF document from any application that can print. Just go and print a document and save it as a PDF instead. Previously most Windows-based PDF tools were either commercial-grade or based around the free Ghostscript technology, so you had to have this installed before you could use a tool that would create a PDF. This has since changed and even companies who produce commercial PDF software are creating lower-end editions, designed for the home user.
doPDF 5.0.214 is a good example, from the developers who gave us NovaPDF 5. It's designed to produce basic PDFs that you can use for displaying on your website or for printing and giving to other users. It installs itself as a printer driver, so any Windows application that can print can produce a PDF.
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Spitzer Space Telescope could not spot Oumuamua, suggesting that it is actually pretty small
Greenland crater one of the 25 largest impact craters on Earth
This long-sought progenitor star was identified in an image captured by Hubble in 2007