What is Cache?

[RichardSmith]

Hello Friends,

Cached means Google has a copy in their "cache" that can be referred to if the URL were to go down. So if a website isn't working you can click on the cache link and pull up an archived copy that Google saved earlier that day.

Thanks and Regards
reputationhead.com

Personal Reputation Management

[convergent]

Bingo 

[frankdevine]

A cache is a block of RAM used for temporary storage of data that is likely to be used again. The CPU and hard drive frequently use a cache, as do web browsers.

In a CPU there can be several caches, to speed up instructions in loops or to store often accessed data. These caches are small but very fast. Reading data from cache memory is much faster than reading it from RAM.

[Sherinfriedler]

A cache (pronounced CASH) is a place to store something temporarily. The files you automatically request by looking at a Web page are stored on your hard disk in a cache subdirectory under the directory for your browser (for example, Internet Explorer). When you return to a page you've recently looked at, the browser can get it from the cache rather than the original server, saving you time and the network the burden of some additional traffic. You can usually vary the size of your cache, depending on your particular browser.

[elenabrown]

Cache is a temporary place to keep a copy of information for faster retrieval on the second request for said information.  You might guess that I would continue on to say that information in this context is nearly anything you want it to be. 
It could be a stretch to say that moving the coffee brewer closer to you is no different than saving a web page onto your local computer so that the next time you need another cup, or need to visit that web page again, it's cached for quicker delivery.

[seo123]

Cache is a snapshot of your site which search engines take and they uses it for judging when a user searches for your site. There are three types of cache. When you look at a cached site its url will be  like eg : http://webcache.googleusercontent.com/search?q=cache%3Ahttp%3A

[Cathrine]

              Caching is used to see cache status of the website.Cache status indicates active participation of crawler on your website.If the crawler is visiting your website daily and changing its database with updates occurred on your website,it means your website is being cached frequently.

[TusharTaliyan]

Cache is the copy of the website that google stores with itself, it also shows when was the last time google's spider crawled that particular page. The 'text only version' can be used to see what a spider is able to comprehend.

[convergent]

So what is difference in catched and indexed sites?

I think this will help:
Indexed pages are cached by search engines
cache is what search engines have in there database and cached pages really compete with each other in search
Indexed is just a page param that says the page was cached by search engine

PS: MikeQ seems to be flooding. I'm watching you!

[nickie snyder]

It is used to increase speed of computer operations, by temporarily placing data in a place or location that is accessible faster than the normal. It is pronounced as KASH, not K-SHAY.