The SIRD model is a type of compartmental model, where the population is divided into four compartments: 1. Susceptible (S): Individuals who are not yet infected but are at risk of contracting the disease. 2. Infected (I): Individuals who have the disease and can transmit it to susceptible individuals. 3. Recovered (R): Individuals who have recovered from the disease and are assumed to have gained immunity. 4. Deceased (D): Individuals who have died due to the disease.