Drupal Administrator Account Management
The administrator account is the username and password you set up when you installed Drupal. This account is your key to the kingdom: The administrator account allows you complete control over everything on your Drupal site.
To change settings for your administrator account, log in and click the My Account link, found on the right side of your site’s home page. You will see basic information about how long your account has existed under the View tab.
You can't configure anything on this page; it simply states your history. To configure the settings of your account, click the Edit tab.
The account settings overlay opens up to reveal a much longer page with options for you to change your status, username, e-mail password, and account password. There are also sections for Theme configuration and Locale settings.
The My Account page and account settings overlay show up for all registered users on your site. They can control their own passwords and, by default, control the same options that your administrator account can change here.