What is the difference between Doc Viewer and PDF Embed?

I am trying to see how to use the PDF Embed when we already have Doc Viewer plug-in. Does Doc Viewer and PDF Embed plug-ins do similar things? How are they different? Is there an advantage for one over the other?

Docs Viewer uses Google, which has some downsides: dependency on Google for one, they also have some limits on the sizes/types/etc of files they’ll show and things like that. Some setups where access to files is limited to logged-in users don’t work well (or at all) with Google Docs Viewer either.

PDF Embed instead uses either the browser’s built in (or plugin provided) PDF support, or a self-hosted Javascript-based viewer.

If Docs Viewer is working well for you, there’s not necessarily a reason to switch (or vice versa).