Use PDF.
The reason for it is that if you print(or watch) a word document on a computer diffrent from the one that created the document,
and that computer have a diffrent printer or miss the fonts you have used to type the letters with, the layout will change.
Text might not fit on the page, some fonts have larger spacing between letters then other and so on.
You could basiclly get 3 diffrent print out from the same document on 3 diffrent computers if you use a non standard font or if you are just unlucky,
and the printer installed changes the document a lot.
With a pdf document, the text will always print and be displayed in the same way, no matter what computer you use,
or what OS it's running: mac, linux, windows and so on. That was the whole reason for pdf in the first place.
(portable document format)
Best is still if you stick to stanard fonts that is common in all systems , otherwise make sure you incorperate the font in to the pdf document
Then it is truly portable an can be read by basiclly all systems, even mobil phones, as long as they have a pdf reader,
And it will always look the same.