Did you know the Google Developer section has an education section for Webmaster Tools at developers.google.com/webmasters?
Fili Wiese, who works at Google on ad quality, but formerly part of search quality, posted this on his Google+ page.
Here is the video followed by the transcript:
0:01 The internet is amazing.
0:03 It's easy to share anything you create with the entire world.
0:07 Like Alice.
0:08 She just opened an online store for her handmade jewelry.
0:11 But now she's wondering, can people find her site on Google?
0:15 With Google Webmaster Tools, Alice can make sure that Google
0:19 finds her store and shows it for the correct search query.
0:23 Webmaster Tools displays the errors that Google finds when
0:26 reading her site so Alice can check those errors and fix
0:29 them to make all her pages appear in search results.
0:33 Every time Alice creates a new product page, she can use
0:36 Webmaster Tool to see if other people link to it and how often
0:39 it appears in Google's search results.
0:42 She can use that data to discover the most successful
0:44 pages and products in her store, so she can focus
0:47 on that and increase traffic to her site.
0:51 Webmaster Tools also regularly checks her site for malware,
0:54 and another problems, and will even send an email if it
0:57 finds important issues.
0:59 Now Alice can be sure that everything is OK with her site
1:02 with Google Webmaster Tools.
Forum discusion at Google+.