Viewer.JS is a combination of a number of excellent open source tools that are built on HTML and JavaScript:
Viewer.js must be the easiest way to use presentations, spreadsheets, PDF's and other documents on your website or blog without any external dependencies. No tricks, no conversions, no unexpected downtime from external services, and no plugins required – it happens to work just fine in all major browsers today from the comfort of your own webserver. Free of cost, free as in open source (so you can tweak it yourself) and very easy to use. Download and unpack on your webserver and add one small text snippet to your webpages. Viewer.js was funded by NLnet foundation, consider a donation.