Earth is the third planet from the sun and the fifth largest in the solar system. Just slightly larger than nearby Venus, Earth is the biggest of the terrestrial planets. Our home planet is the only planet in our solar system known to harbor living things. The name Earth is at least 1,000 years old. All of the planets, except for Earth, were named after Greek and Roman gods and goddesses. However, the name Earth is an English/German word, which simply means the ground.
Picture: Voyager 1's view of Earth from a distance of about four billion miles (6.4 billion km).
NOTE: Above information has been taken from wikipedia and/or official websites of topics.