Dark Matter is an extremely common substance composed of elementary particles called Darkons. These Darkons exclusively are affected by gravity and are unaffected by all other forces. Dark matter is also unexploitable, and many disappointing results have been made in attempts to.
Dark Matter is composed entirely of Darkons. Darkons are extremely massive subatomic particles (mass is approximately 25 u) which only interact with each other and normal matter via gravity. Darkons are non-Fermion particles, which means that they are neither quarks nor leptons. Instead, they are a separate class of particles unto themselves.
Dark Matter makes up about 85% of matter in our universe, and on average, makes up 83% of all other observed universes. The particles congregate around galaxies and in galaxy clusters throughout the universe. These particles are unable to congregate and form objects, as they only interact through gravity. This makes forming bodies impossible due to their tendency to speed up when in high gravity situations.
There are approximately 4.8e^78 Darkons in the universe. Most of which orbit large galaxies and clusters. There is estimated to be quadrillions of Darkons orbiting the sun, but the number is likely larger due to the difficult to detect nature of the particles.