Blogger comes with a default navigation bar.This blogger navigaton bar may not be present in most of the templates.But if you are using a default blogger template,then you will see some navigation bars like the one in this picture.These navigation bars can be removed using some simple CSS techniques.

Here are the steps to remove the Blogger Navigation bar /Blogger Nav Bar :

1. Login to your blogger account
2. From your Dashboard click on Design
3. Now choose Edit Html
4. In that template code find ]]></b:skin>
5. Add the below code Just before ]]></b:skin>

   #navbar-iframe {display:none !important;}

   #navbar-iframe {display:none !important;}

6. Then Click on Preview and if everything is right hit the Save button