The Epstein-Barr virus (EBV) is a common virus that belongs to the herpesvirus family. It is best known for causing infectious mononucleosis, often referred to as "mono." Many people are infected with EBV during childhood or adolescence, and while it can lead to symptoms like fatigue, fever, and sore throat, most recover without serious complications. Once a person is infected, the virus remains in the body for life, usually in a dormant state. In some cases, it can reactivate and may be linked to certain conditions, such as Hodgkin lymphoma and nasopharyngeal carcinoma. Understanding EBV is important for managing its potential health impacts.