This is useful for SEO (Search Engine Optimization). This module used to be called the MetaTags Module now in Drupal version 7 it is called the NodeWords module.First you must know the version number of your Drupal. This can be found by going to your website and logging on as the Administrator. Next navigate to Administration >> Reports >> Status Report This will display a list at the top it says Drupal followed by the version number that is currently installed.
For Drupal 6xx users install Node words module
Download below the release of the Nodewords module. Extract the files and you are eft with a folder called Nodewords this folder will contain many files and subfolders. Copy that file over to the server using FTP, SCP, SSH, or any other method you prefer copy the Nodewords folder from your computer to the server in the folder where Drupal is installed navigate to the modules folder now copy the Nodewords
Now to make it work go to the webpage where drupal is and navigate to Administration >> Site Building >> Modules >>
Now scroll down to Meta Tags and enable everything under it then save.