Common app user name? Unique?

Applying to College Common and Coalition Application
1

<p>Should this be unique (that is not so far used by anyone say for eg like gmail or yahoo id) . Does it say "user name not available" if its already used by someone?</p>

<p>If not, how does it work?</p>

<p>thanks</p>

2

<p>It’s like every other web site that requires a log-in. If the name is taken you can’t use it. Your username’s irrelevant to admissions as long as the apps are sent.</p>

3

<p>It’s just like CC. you sign up with a screen name and thats what you log in with. For example, last year I tried to use abbygirl130, however it was taken so I chose something else</p>

4

<p>list down colleges or university that require supplement
2.can the student using the common app mix and match their application,supplement,and payment by submitting some online and some by paper?
3.only holistic that uses a holistic selection process can apply to be members of commonapplication. what does holistic selection process ?
4.what are the advantage of using of common application?</p>