Introduction.- Philosophical Motivations.- Kochen-Specker Theorem.- Introducing Category Theory.- Functors.- The Category of Functors.- Topos.- Topos of Presheaves.- Topos Analogue of the State Space.- Topos Analogue of Propositions.- Topos Analogues of States.- Truth Values.- Quantity Value Object and Physical Quantities.- Sheaves.- Probabilities in Topos Quantum theory.- Group Action in Topos Quantum Theory.- Topos History Quantum Theory.- Normal Operators.- KMS States.- Future Research.- Topos and Logic.- Worked out Examples. sakriti opis