Magento: Show/Hide website to search engines by adjusting robots meta tag

The Robots META Tag is meant to provide users who cannot upload or control the/robots.txt file at their websites, with a last chance to keep their content out of search engine indexes and services.

<meta name="robots" content="robots-terms">

The content=”robots-terms” is a comma separated list used in the Robots META Tag that may contain one or more of the following keywords without regard to case: noindex, nofollow, all, index and follow.

noindex = Page may not be indexed by a search service.
nofollow = Robots are not to follow links from this page.

You can find more about the robots meta tag over here: http://www.seoconsultants.com/meta-tags/robots/
There is an easy way in Magento to adjust robots meta tags. You can simply choose from admin settings.
Go to System -> Configuration -> Design -> HTML Head -> Default Robots
You have the following options to choose:

- index, follow
- noindex, follow
- index, nofollow
- noindex, nofollow

If you have a live site (production site) then choose ‘index, follow‘. If you have a test site (development site) then choose ‘noindex, nofollow‘.
Hope it helps. Thanks.

Magento: Show/Hide Demo Store Notice

A demo store is where there are products but the order done by customer is not processed. If your website is in development mode then it is better to enable demo store notice.
Enabling demo store notice in Magento is very simple. You just need to select an option in configuration settings in admin panel.

Go to System -> Configuration -> Design -> HTML Head -> Display Demo Store Notice
By default, it is set as ‘No’. To enable demo store notice, select ‘Yes’.
Now, you will see a notice bar at top of your page saying ‘This is a demo store. Any orders placed through this store will not be honored or fulfilled.‘
Hope it helps. Thanks.