<p>What you are thinking of is “Early Decision.” You only get to apply to a single university in the Early Decision round because you are making a commitment to attend if accepted.</p>
<p>Rolling admissions means that applications get read on a continual basis. If you apply in August, you might get a decision by September. That’s in contrast to colleges with a strict application deadline (most of the top universities fall into this categories): they will read all applications together after the deadline.</p>
<p>Colleges with strict application deadlines don’t care how close to the deadline your application gets submitted: you won’t get your decision any sooner and it won’t improve your chances. However, the date that your application gets submitted does matter with rolling admission schools because there will be fewer open spots left the longer you wait.</p>
<p>You can apply to as many rolling decision schools as you like. (As long as you are not signing an Early Decision agreement, of course.)</p>