The disc is composed of 2 parts; the outter tough annulus & inner soft nucleus.
They serve as shock
absorbers between 2 vertebra & assist in guiding motion. A protrusion is a bulging of the disc when there is weakness of the annulus. The annulus weakness may result in tears of the layers of the annulus that are called fissures. Weakness of the annulus may lead to the nucleus material oozing out.