"Dark Matter & Dark Energy
In the standard Lambda-CDM model of cosmology, the mass–energy content of the universe is 5% ordinary matter, 26.8% dark matter, and 68.2% a form of energy known as dark energy.
Thus dark matter constitutes 85% of the total mass, while dark energy and dark matter constitute 95% of the total mass–energy content.
The leading explanation is that dark matter is some as-yet-undiscovered subatomic particle. The other main possibility is that dark matter is composed of primordial black holes."