1. Digital Versatile Disc (DVD), sometimes also known as Digital Video Disc (DVD), is an optical disc storage media format for storing digital data.

2. DVD offers higher storage capacity than compact disc (CD) when having the same size.

The Earth is not a perfect sphere but is slightly flattened at the poles and bulging at the equator due to its rotation. This shape is often referred to as an oblate spheroid, meaning it is mostly spherical but slightly flattened at the poles and slightly bulging at the equator. The flattening is a result of the Earth's rotation, which causes it to be slightly compressed along its axis.