Google Webmaster Tools is a free, no-charge web service by Google for webmasters. It allows webmasters to check indexing status and optimize visibility of their websites. Some of its uses includes submitting and checking sitemaps, set the crawl rate, and view statistics about how Googlebot accesses a particular site, as well as generating and check a robots.txt file. It also helps to discover pages that are blocked in robots.txt by chance. It can also list internal and external pages that link to the site, get a list of broken links for the site and see what keyword searches on Google led to the site being listed in the SERPs, and the click through rates of such listings. Other of its functions are :
- Viewing statistics about how Google indexes the site, and if it found any errors while doing it
- Setting a preferred domain (e.g. prefer example.com over www.example.com or vice versa), which determines how the site URL is displayed in SERPs
- Highlighting to Google Search elements of structured data which are used to enrich search hit entries (released in December 2012 as Google Highlighter
- Receiving notifications from Google for manual penalties.
However, The list of in bound links on Google Webmaster Tools is generally much larger than the list of inbound links that can be discovered using the link:somewebsite.com search query on Google itself. Google is tight lipped about the discrepancy. The list on Google Webmaster Tools includes nofollow links that do not convey search engine optimization authority to the linked site. On the other hand, the list of links generated with a link:somewebsite.com type query are deemed by Google to be “important” links in a controversial way.
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