his plugin helps you Improve your application performance with browser caching, with easy ways to set caching headers in controller responses, and elegant ways to deal with ETag and Last-Modified generation and checking. You can use this plugin to prevent caching of pages (eg forms), specify long term caching on infrequently changing content, and pass information to caching servers between the client and your app, and also to avoid regeneration of content if it has not changed since the client last downloaded it (even though the client may have an indication it has expired).
See the documentation for more information