Asteroids are naturally occurring solid or rocky materials that orbit the sun. They orbit the sun in a way very similar to how planets move around the sun. Asteroids are part of the solar system, but they are not the same as the planet, in fact, they look very smaller compared to the planets, and they are not comets either.
Although there are some asteroids that move around the sun in the same orbital path of the planets, the majority of them exist between the orbit of Jupiter and Mars. Also, there are some asteroids that exist in the orbit of Earth and some other planets, but they are not as much as those found between the orbit of Jupiter and Mars.
According to researches, asteroids are small portions that were left over after the formation of the solar system, which is about many billions of years ago. Another interesting thing about asteroids is that no two asteroids look the same.