A nosebleed, or epistaxis, occurs when the blood vessels in the lining of the nose break, leading to bleeding. This can happen due to various reasons, including dry air, allergies, or injury. Most nosebleeds are not serious and can be managed at home. There are two main types of nosebleeds: anterior and posterior. Anterior nosebleeds, which are more common, originate from the front part of the nose. Posterior nosebleeds come from deeper within the nasal cavity and may require medical attention. Keeping the nasal passages moist can help prevent nosebleeds.