A transmmissive display will have a transmissive front polarizer & a transmissive rear polarizer,a backlight is required.
A reflective display will have a transmissive front polarizer & a reflective rear polarizer.
The reflective layer that is behind the rear polarizer can reflect the incident light so that the user can make use of the ambient light, backlight is not required.
A transflective display will have a transmissive front polarizer & a transflective rear polarizer, the transflective polarizer can let portions of the incident light pass through and reflect the rest. Therefore, transflective LCD can be operated similar to a transmmissive display when the backlight is turned on, or similar to a reflective display when the ambient light is enough.