Quantum-based materials calculations are primarily simulation activities because they start from the theory. Unlike purely theoretical work, which may derive fundamental principles or concepts, these calculations aim to model real-world materials and predict their properties using substantial computational resources.

Many people may intuitively view quantum calculations as theoretical because they involve fundamental physics principles and equations, such as the Schrödinger equation. This perception stems from the common association of theory with the derivation of laws, while simulations are often seen as applied or practical efforts that may lack the abstract elegance of theoretical derivation.