Scientifically how does a cd work

May Data on a CD is encoded with the help of a laser beam that etches tiny indentations (or bumps, if you will) on its surface. A bump, in CD. A digital videodisc, or DVD, looks like a CD but is more advanced. DVDs are often used to store movies. How a CD Works. The CD is forecast to remain the mainstream format for music for some years to development work on digital discs should be channeled into 12 directions.