You must have official transcripts sent that reflect all undergraduate and graduate work that you have completed or is in progress. If there was a single course that you took at a community college years ago, ask them to send a transcript. The University can get very upset if they discover that your transcript record is incomplete.
Transcripts indicate many things. For one, they show any degrees that you have completed. They show what courses you have taken, and therefore give some indication of your background. A heavy courseload with high grades shows a strong work ethic. Of course, the number on a transcript that prospective students ask about most frequently is their grade point average (GPA).
The Graduate School requires that your GPA be at least 3.0. The average GPA of entering supported students is usually between 3.6 and 3.8. The average GPA of all entering students is usually between 3.5 and 3.7. While there is no GPA "cut-off" above 3.0, if your GPA is significantly below these averages, your chance for admission or support goes down. A high GPA for more recent and advanced courses will compensate for a low GPA early in your college career. Students who are admitted whose GPA is below average often have other components of their application that are stronger than average.