Academic audit

In academia, an audit is an educational term for the completion of a course of study for which no assessment of the performance of the student is made nor grade awarded. Some institutions may record a grade of "audit" to those who have elected not to receive a letter grade for a course in which they are typically awarded.
In this case, 'audit' indicates that the individual merely has received teaching, rather than being evaluated as having achieved a given standard of knowledge of the subject. The term 'audit' is Latin, translating as, 'he/she hears'. In other words, the audit student has experienced the course, but has not been assessed.
Some students audit a class merely for enjoyment, including purposes of self-enrichment and academic exploration, with no need or desire of academic credit. Sometimes this technique is employed by individuals who wish to take a specific course without the risk of under-performance resulting in a poor or failing grade. This may be helpful when reviewing a long-unstudied subject, or when first beginning or exploring the study of a discipline where one has little experience or confidence.
Auditing is generally an option at institutions of higher learning, such as colleges and universities, rather than grammar school or secondary school.