Are you not a fan of Chrome’s built-in PDF viewer? Or perhaps you don’t like the idea of Adobe Flash being bundled with the browser. You don’t have to live with these built-in plugins, you can disable them. Here’s how.
In the Chrome address bar type chrome://plugins
On the Plug-ins page there will be two options for each plugin, Disable and Always allowed. What each one does is self-explanatory.
Additionally, if you want to find out a ton of details about every plugin the Details button will reveal all. Some of the plugins may have 2 files listed, and the settings for these will only be available if the details box is expanded.