Why is earth called a blue planet?

The third closest planet to the sun is the earth. The planet looks blue from outer space since two-thirds of the surface is covered with water, so it is called a blue planet. That is 71% of the earth is covered by water. It is the fifth-largest planet in terms of size. On the poles, it is slightly flattened. The form of the Earth is defined as a geoid. Conditions conducive to sustaining life are only likely to be found on earth. It has air and water, which are very important in life. The air has life-supporting gases like oxygen. When looked at from the space it appears blue due to those water bodies.