Does The Same Stylesheet Get Loaded Multiple Times On Different Pages?

Question

I work on a large Intranet system - as it is an evolved system which started over ten years ago unfortunately the design of it isn't great and needs to be completely rewritten as it currently works by using frames.

The problem with the frame-based layout is that there's a "main" section which does the includes for the stylesheets. This is quite a simple question, but I've never found any evidence of it. Does that same stylesheet get loaded multiple times because it's on separate web pages? Or does the browser cache it and do a comparison check against same-named stylesheets. Is this the same for JavaScript libraries?

Answer 1

Yes, browsers will load external scripts and stylesheets from cache for each frame, unless you deliberately break it by sending no-cache headers with those files.

Answer 2

AFAIK the browser should always query its cache before making a http request (GET).
'always' being the operative word as we all know the problems with what browsers should and shouldn't do!
This rule should apply to any filetype that is requested by the browser.