Links are important for driving traffic to your site. More often than not, it's difficult to keep track of who is linking to your site. I've seen many solutions in my time: from manually keeping track with spreadsheets, to using the "link:" operator in Google, to even resorting to parsing web logs. I find, however, that the most efficient method of managing these links is using Google Webmaster Tools.
The link reports in Webmaster Tools take advantage of Google's crawler, affectionately named Googlebot, and make use of almost every link that it has discovered to date. Googlebot crawls the web in order to understand what content is out there. It's during this crawling process that it discovers publicly-accessible links to your site. This information is then made freely available to you through Webmaster Tools.
Pages with external links
This report shows you where external links (i.e. links from outside of your domain) to your website are coming from. It shows you (a) which specific pages are being linked to, and (b) where those links came from.
Pages with internal links
This report shows you how your pages are interconnected internally (i.e. from within your website).
Not found links
There is an extremely useful report in "Diagnostics > Web crawl" that shows you URLs on your site which return a 404 error, which may or may not be due to broken external links. Thanks to a recent update, this report now also shows you where Googlebot found links to these URLs. You can take action based on this information: (a) 301 redirect any broken URLs to a working URL; (b) request a fixed link on the originating page; and (c) add an enhanced 404 page at the broken address.
These are a few ideas on how you can use Google Webmaster Tools to discover, manage and maintain links to and within your website. If you have additional tips, we would love to hear about them in the comments below.
Handy hint: as you are navigating the reports in Webmaster Tools, click on the "How do I use this data?" link to learn more about how to use the data within a report to take actions that will benefit your website.
For more information on Webmaster Tools and links to many other resources, check out Google Webmaster Central. Here you'll find our official blog, forum, and help documentation ... all for webmasters!
Posted by Vinoaj Vijeyakumaar, Customer Solutions Engineer