If you look closely here,you should see the warning message. It's a very technical work here in that this is the place you decide the fate of your blog or certain articles with the world wide web. Google and other search engines represent the key way you get unique/potential users of your articles to come and read by
publishing this stuffs on-line and then asking or permitting search engines to index/catalogue them into their. call it ''library'' for showing to people that visit them to look up for such write-ups. And just here is the place for disallowing or granting that your blog and it's content be crawled by web crawlers.This Place Is to be used/touched by a webmasters only,Note!!!
Now for robots.txt,
visit http://your blog adress/robots.txt that will show you what you now will copy and paste into this robots.txt option. What they will show you will look exactly like :
User-agent: Mediapartners-Google
Disallow:
User-agent: *
Disallow: /search
Allow: /
Sitemap: http://bloggerdemmy.blogspot.com/feeds/posts/default?orderby=UPDATED
Just past it their and click done