There are seven reason of add ur web site in webmaster tools
a) Go to Google Search Console (previous Google Webmaster Tools), sign into your Google record and tap the red catch to include your site.
b) Once you've tapped the catch to include your webpage, simply sort your site's URL in the...
Crawling is something like Search engine bots visited your site and indexing is saving your information in database and caching is the more detail information of indexing like when visited and time , now you can know which goes first.