If you are a newsource user, you can login to your account to access all of your services. If you have not yet registered for an account, you can do so by clicking the "register" link on the login page.
There is not much to say about newsource login services, other than that they are a way for users to login to a newsource account.
If you are a newsource user, you can login to the site using your username and password. If you are not a newsource user, you can create an account by clicking the "create account" link on the login page.