There are LOTS of different Usernames and Passwords involved with 'Domain Name Registration and Website Hosting', and it can be confusing as to what goes where.
1) First - your client account (your billing & invoice & overall 'management' account) is based on YOU as a customer, so the login user there is your email address. When you are logging in as a customer (for example - to order new domains/services, to renew domains/services, to cancel domains/services, to open/reply to support tickets, to pay for invoices, etc) then you'll want to log in at http://www.9DollarDomains.com/billing and again, these sorts of things are based on the customer, so you'll log in as YOU, using your email address and the password that was created for your billing area. It's helpful to remember that one Client/Billing account may only have a single website, but it could potentially have many (even hundreds) of domains & hosting items in it's inventory. The single customer account can administer the renewal or invoices or support tickets for everything it that customer's inventory.
2) Second, each website in your inventory will have it's own separate Control Panel (CPanel) login for the configuration & for the uploading of content to that website. Again, many clients only have a single website, but some clients have 10 or even 100's of websites in their inventory, and each one will have it's own CPanel/FTP username and it's own password.
3) Third, each website can also have email addresses associated with it - anywhere from one or potentially 100's of emails for each domain name, and every one of these email addresses will have their own separate usernames and passwords. If you think about it, the Usernames and Passwords for an email account are used for a totally different purpose than the username and password for the website's CPanel - and those email user/pass credentials will be totally separate from the Cpanel User/pass's or from the Client User/pass's.
4) Fourth, in a website, you may also have programs & scripts - such as blogs, forums, shopping carts, CMS's (like WordPress), Calendars, etc - and each of those may have their own username's and passwords. If you setup OSCommerce as your shopping cart online store, during it's setup it may ask you to create a password, and that password will be for the Administration of the Shopping Cart - so if your website has several programs like that installed on it, it's possible that you'll have several more usernames and passwords - since each program may needs it's own.
ALSO - it's important to remember that in most cases, most of these passwords are hidden & encrypted and we have no idea what they are. In many cases, these are just as encrypted and hidden for us, as they would be for any hacker - so write them down and keep them safe. If you forget them, we may have no ability to look them up, or to even figure out what they are. In some cases, we are able to arbitrarily set a new password for you, which can be a solution in some situations, but we rarely have the ability to look up or to decode an existing password.
So, the need for all these separate uernames and passwords can seem confusing - expecially for the client that only has a single domain, a single website, and a single email address. However, if you keep in mind that the internet is filles with billions of people & websites, it makes more sense why hosting providers need to assign multiple logins, depending what you are trying to do. You need to be able to identify who YOU are (client profile login using email email/password), how to upload content to your website (website login using your CPanel/FTP login/password), how to fetch your domain email (email login using each email addresses username/password) and possibly also how to administer your Blog or Shopping Cart scripts (script login using it's username/password).
