The Blue Planet
Earth is the third planet of the solar system, which means it is a terrestial planet. This planet is obviously known for being home to life. It's average temperature is around 59ºF. This puts the planet as the third warmest planet of the solar system. (1st: Venus (around 870 deg. fahrenheit), 2nd: Mercury (~ 800 deg. fahrenheit)). There is exactly 1 AU distance from the Sun.
In the 16th century, that was the time humans believed Earth was an actual planet. The Egyptians and Sumerians observed that the Earth was spherical, and not the current theory that the Earth was flat. Copernicus also observed and came to the conclusion (that lead to the truth) that Earth isn't flat and is not the center of the solar system. In fact, he assumed that the Sun was not the center either - there was no center.
As we all know, there are TONS of physical features on Earth. Some include: Indian Ocean, Mount Everest, Asia, Pacific Ocean, North Pole, South Pole, Himalayas, Caspian Sea, Fault Block, Challenger Deep, and TONS more!
Earth's core mainly consists of iron-nickel alloy, with trace amounts of other elements.