Earwax is a build-up of dead cells, hair, foreign material such as dust, and cerumen. Cerumen is the natural wax produced by glands in the ear. It forms a protective coating of the skin in the ear canal. Small amounts are made all the time. Flakes or crusts of earwax break off and fall out of the ear from time to time.
The quantity of earwax made varies greatly from person to person. Some people form plugs of earwax in their ear canal. This may cause a feeling of fullness and dulled hearing. A hard plug of earwax can also sometimes cause 'ringing in the ear' (tinnitus) or even a mild type of dizziness (vertigo).