Names, like many words have origins and sometimes those origins include stories. The planets were named after Greco/Roman gods (all except earth which is simply named ground). Each planet is named after a specific god for a reason and those reasons teach us something about the planet, whether it is placement, color, or size; the story of the name is an informative way to learn about the planets and the archetypes that inspired the names.
Mercury is the closest planet to the sun. His Greek equivalent is Hermes. He is known as the messenger to the gods because he is the fastest god. Since Mercury is the fastest god, the fastest planet was given his name.
Venus is the next planet. Venus is the brightest planet and for that reason it is thought of as the prettiest. Venus is the only planet named after a goddess. Her Greek equivalent is Aphrodite, the goddess of love and beauty.
Earth just means ground, only one not named after gods/goddess.
Mars is named after the Roman god of war and associated with bloodshed and war because of its red color. His Greek equivalent is Ares.
Jupiter is the largest planet so it was named after the most powerful god, Jupiter. His Greek equivalent is Zeus.
Saturn is the farthest planet able to be seen with the naked eye. It was named after Saturnus, the father of Jupiter and the god of time.
Uranus is first planet to be discovered by telescope. It is named Uranus after the god of the sky. Uranus is the Greek equivalent to the Roman god Caelus who is father to Saturnus and grandfather to Jupiter. The reason for the shift from Roman to Greek is unknown and solitary as the rest of the planets are named after the Roman gods. It was the first planet to be discovered in 5,000 years.
Neptune is named after the god of the sea, Neptune. His Greek equivalent is Poseidon. The planet was given this name because it is a blue planet and blue is the color of water.
Pluto has had some controversy over its status as a planet but when it was named, it was considered the farthest planet from the sun. It was named after Pluto, whose Greek name is Hades, the god of the Underworld. Since it was the farthest planet from the sun, it is also the coldest. It makes sense to name the planet after the lord of the underworld, a cold, dead place.