Auditing a course gives you the chance to attend a college class as an observer without the pressures of working for a grade. Since many colleges require students to be enrolled in classes even as visitors, people often audit courses to learn about subjects that aren't required for their majors or to review an area in which they already have some knowledge. While you aren't taking the course for credit, you'll still be required to attend class and possibly complete some assignments and be active in the classroom community.
Students who want to audit a class typically must get permission from the instructor before registering. Some colleges have specific policies about what courses can and cannot be audited; for example, graduate classes may be restricted to students pursuing a degree, while classes on writing and performing arts classes or laboratory activities may not allow visitors. You will most likely be required to meet with the instructor to discuss your reasons for auditing and complete signed paperwork giving you authorization to sit in on the class.
Universities usually give priority in registration to students who are pursuing a degree and need the class to graduate. Because of this, you may have to wait until the end of the designated period for adding courses to register for the class you want to audit. If available slots are open in the class, you'll then be able to officially join. If you're pursuing a degree at the university but still want to audit a course, make sure you won't eventually have to take the class for credit, as your school may not allow you to enroll again for a grade. Check to see if your college requires auditors to pay fees for visiting classes, and be sure to pay them on time.
Come to Class
You may not be taking the class for credit, but you won't get anything out of your auditing experience if you don't attend class. Many universities even make auditors subject to the attendance policies for the courses they're in; if you don't consistently come to class, the instructor may reserve the right to remove you from the class list. Note any special conditions for class attendance that apply to you as an auditor and talk with the instructor about his expectations beforehand, as well as any assignments he would like you to complete or participate in.
Practice Auditing Etiquette
Since college courses are mainly for the benefit of students taking them for a grade, your primary duty as an auditor is to observe, not to contribute. While the instructor may allow you to participate in class under certain circumstances, be aware of when it is OK to speak up and when you should just listen. Respect the needs of students who are taking the class for credit by arriving on time, paying attention and not causing distractions.