What is a Noindex metatag?
If you want to entirely block your website from search engines and prevent your page from coming up in the search engine results, you would use the noindex meta tag in the head section of the pages you wish to block. It allows you to control access to your site on a page-by-page basis.
When search engine crawlers see a 'noindex' tag, they avoid indexing the page so it doesn't turn up in search results. While Google, Yahoo and Bing all support the use of 'noindex' tags, some search engines do not, therefore your website can still appear in search results.
There's also a chance that the search engine spiders won't see a 'noindex' tag, and your page is still appearing in results. This could be because the page hasn't been crawled in a while, or you are using a robots.txt file. The content will be removed the next time the page is crawled, or if you want remove a URL immediately, you can submit a URL removal request.
How to use it
To prevent all robots from indexing a page on your site, place the following meta tag into the <head> section of your page:
<meta name="robots" content="noindex">
If you just want to block your website from Google, use the following:
To allow other robots to index the page on your site, preventing only Google's robots from indexing the page:
<meta name="googlebot" content="noindex">
More variations of the meta tag
More information on the Nofollow metatag can be found Nofollow.
<meta name="robots" content="noindex, nofollow">
The spider will NOT look at this page and will NOT crawl through the rest of your webpages.
<meta name="robots" content="noindex, follow">
The spider will NOT look at this page, not index it, but will crawl through the rest of the pages on your website.
Index, No follow
<meta name="robots" content="index, nofollow”>
The spider will now only look at this page, index it in its search engines, but it will NOT follow any links on this page.