All instructors will post a syllabus during the first week, which will include class policies, including attendance policy. In most classes there is a penalty, often a significant one, beyond a certain number of absences. Most instructors do not discriminate between "excused" and "unexcused" absences, so it is wise to save the allowed absences for when you really need them. If you find that you must miss or have missed more times than allowed, SEE THE INSTRUCTOR right away. In some cases it is best to take a withdrawal from the course. Sometimes an Incomplete may be given. DO NOT JUST GIVE UP AND DISAPPEAR. If you are uncomfortable going to your instructor, see your advisor or another faculty member in the Department. If you decide to drop a course, please notify the instructor.
See the University calendar for the last date to drop a course without an academic penalty. After that date, you will usually receive a grade of WF, which counts as an F in your gpa. There are some exceptions to this (including medical withdrawals and some extenuating personal problems), so contact the office of Student Academic Services for details. (Details at http://web.uncg.edu/adv/drops.php).
If you are on financial aid and considering withdrawal, be aware that you must pass 75% of the classes you are enrolled in at the end of the first Friday of classes each semester, or you are likely to lose your financial aid.