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When browsing to a website, "who" makes makes the choice of determining whether to pull a webpage from the local cache or from the server? Is it the browser? Web server? Webpage-specific coding?

How is this determination made?

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Completely different questions, although within the same arena of subject -- How a user can see whether a particular page is a cached or live view, versus the inner workings/underpinnings of the technology/functionality -- Is the browser (typically) making such decision by doing a bit-by-bit comparison? Is the server monitoring IP/cookies/access times? Is the OS/server/browser surveying local memory/hard-drive cache? etc. – Coldblackice Jul 1 '13 at 21:00

Proxy servers are known for their caching features. Maybe you are behind one.

Also many search engines will ask you if you would like to load a cached version of a page if your internet is slow and failing to render the more recent data.

Somewhat of a problem considering most content is so dynamic these days.

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I don't think this really answers the question of how the computers decide whether to serve up a fresh copy or a cached copy of a webpage. – nhinkle Jul 1 '13 at 20:47
He didn't ask how the computer decides, he asked "who decides" I listed some very valid "who's" – Scandalist Jul 1 '13 at 20:52
@Scandalist Thanks (I'm not the one that downvoted). I'm not behind a proxy server, however. I'm asking on a general "protocol"-type level. It's my newfound understanding that "someone" (browser/server/operating system/webpage) is making a decision on whether to load a respective page from local cache, or whether to request it fresh from the server (i.e. HTTP Error 304). It apparently happens on a behind-the-scenes, protocol level, with no active intervention required from the user. I'm trying to determine "who" is making this decision, and the methodology of such decision. – Coldblackice Jul 1 '13 at 21:07
@Coldblackice perhaps "what" would be a better wording, to clarify that you're not asking which person ("who") but rather which device ("what")? – nhinkle Jul 1 '13 at 21:33
@nhinkle That's why I put "who" in parentheses, but you're right, it is still confusing. I'll update. – Coldblackice Jul 2 '13 at 2:56

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