Say: "It has been revealed to me that a company of the jinn gave ear, and they said: 'We have heard a wonderful Qur'an, which guides to righteousness, so we believe in it and we shall not join (in belief and worship) any (gods) with our Lord. And (we believe) that He—exalted be the glory of our Lord—has taken neither wife nor son .... Among us there are righteous folk and among us there are far from that. We are sects having different rules." (72:1-3, 11)
Given this, we can understand that jinn are conscious beings charged with Divine obligations. Recent discoveries in biology make it clear that God created beings particular to each realm. Jinn might have been created while the Earth was still a body of fire. They were created before Adam and Eve, and were responsible for cultivating and improving the world. Although God later superseded them with us, He did not exempt them from religious obligations.
The Qur'an states that jinn are created from smokeless fire (55:15). In another verse, it clarifies that this fire is of a scorching wind (15:27) and penetrates as deep as the inner part of the body. 
Like angels, jinn move extremely fast and are not bound by the time and space constraints. However, since the spirit is more active and faster than jinn, those who live at the level of the spirit's life and can transcend the limits of matter and the confines of time and space, can be quicker and more active than them. For example, the Qur'an relates that when Prophet Solomon asked who could bring the throne of the Queen of Saba' (Yemen), one jinn answered he could bring it before the meeting ended and Prophet Solomon stood up. However, a man with a special knowledge from God replied: "I can bring it to you quicker than the blink of an eye," and he did so (27:38-40).
As nothing is difficult for God Almighty, He has provided human beings, jinn, and angels with the power and strength appropriate for their functions or duties. As He uses angels to supervise the movements of celestial bodies, He allows humanity to rule the Earth, dominate matter, build civilizations, and produce technology.
Power and strength are not limited to the physical world, nor are they proportional to bodily size. We see that immaterial things are far more powerful than huge physical entities. For example, our memory is far more spacious and comprehensive than a large room. Our hands can touch a very near object, but our eyes can travel long distances in an instant. Our imagination can transcend time and space all at once. Winds can uproot trees and demolish large buildings. A young, thin plant shoot can split rocks and reach the sunlight. The power of energy, whose existence is known through its effect, is apparent to everybody. All of this shows that something's power is not proportional to its physical size; rather the immaterial world dominates the physical world, and immaterial entities are far more powerful than material ones.