Joined: 28 Apr 09
09 Nov 12 2:35 am
Webmaster tools provides you with more technical information about your website, such as broken links, incorrect code, etc., but it does have some overlap with Google Analytics which provides visitor statistics (how visitors find your site, what pages they view, for how long, etc.).
Used together they can give you vital data on your site which you can use to see what's working and track improvements.