If any of you have used Windows, you will know that creating PDF files usually requires installation of extra software etc. On the Mac, this is not the case. PDF has been very nicely integrated with the Operating System (Mac OS X) so that all you have to do in order to create one is tell your Mac that you want to print.
But - instead of actually printing the document, you select Save As PDF... from the menu located at the bottom of the print dialog box.
This allows you to save the file wherever you like, naming it as you like and it is automatically created in PDF format. You can then email it or whatever you wish to do with it.
PDF stands for Portable Document Format and it's a lovely way to exchange data as it saves your document in a read-only format that can be viewed on just about any device. Almost all users would have Adobe Acrobat Reader installed nowadays, which is what you generally use to view PDF files. The Preview app that comes with Mac OS X is also an excellent choice and very easy to use.