This a common question among people who buy store-bought tortillas and are dissapointed with the dry texture and how easily they tear. If you make your tortillas fresh you won't have that problem as they will be warm and chewy. However, time constraints often cause us to get by with a store bought version. If you suffer from dry, stiff tortillas, there is a solution. Read How to Heat Flour Tortillas
and have softer tortillas next time you make tacos.