Earth is the third planet from the Sun and the only object in the Universe known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago. Earth's gravity interacts with other objects in space, especially the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in 365.26 days, a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times.
The world is the planet Earth and all life upon it, including human civilization. In a philosophical context, the "world" is the whole of the physical Universe, or an ontological world (the "world" of an individual). In a theological context, the world is the material or the profane sphere, as opposed to the celestial, spiritual, transcendent or sacred spheres. "End of the world" scenarios refer to the end of human history, often in religious contexts.
What have we done to the world, look what we've done
What about all the peace that that you pledge your only son?
What about flowering fields, is there a time?
What about all the dreams that you said were yours and mine?
Did you ever stop to notice all the children dead from war?
Did you ever stop to notice the crying Earth, the weeping shores?
Michael Jackson, "Earth Song" (1995).