This form is used to request and manage accounts for the TeX Live Subversion repository. Changes are not immediate, but are sent to an administrator for review. If you are not already known as a TeX Live developer to Karl and Kaja, please email us first about what you'd like to volunteer to do, etc.
Subversion requires that your password be stored in clear text on the server; therefore it is visible to the system administrators. So do not use a password that can be used to access other accounts of yours, including any account on tug.org. Of course it will not be accessible to any users on the server, nor ever sent in the clear over the Internet - it's only Subversion itself that will access it.
If you have already set up an account, and have now forgotten your username and/or password, just fill out this form again as best you can, and we will help you get going again.
If all you want to do is look at the sources, not commit changes, you don't need to fill out this form.