Why caching is done in google? Do the page that we get after clicking at a link on on SERPs is a cached page?
Caching is done so that the site can be analyzed - for duplicate content, links, etc. This cannot be done on the fly. The main link you click on is not a cached page, unless your access provider or local system is set up to cache on its own. There is a little link at the bottom of the description that says 'cached'... clicking on that shows the info that Google cached for analysis, and the date it was cached.
On this subject - does any one know why Google would cache pages from a fairly regular site [approx 100 pages] on several different days and, not relating to the structure of the site i.e. not due to navigation or strange methods of linking. I've been studying this recently and also noted that the cache took 2-3 days to show in the SERPS - is this a common occurence?
A good use of Cached pages for us normal surfers is this- For example, you are searching for something and a Google Result shows up, you click and get a 404, however the information you want exists on that page as shown by the search result, so you can just see the cached version and take the information you need! It has helped be thousands of times with find the info I wanted IT
It's not uncommon. It does take some time once the the data is gathered before it goes live. It's not an instaneous thing. 2-3 days seems about right. Dave