what are the CUNY assessment tests?

<p>I got a letter from a CUNY college that admitted me,it says I need to take the tests.
I do not know anything about these tests, how important are they? how many I need to take? am I taking these tests for all the CUNY I applied or individually? what if I fail?<br>
I don't think I can finish asking all of my questions in one day .....</p>