differance between twilight and dusk

Twilight - the soft glowing light from the sky when the sun is below the horizon, caused by the refraction and scattering of the sun's rays from the atmosphere. Dusk - the darker stage of twilight.

Twilight is the period between sunset and dusk. During twilight there is still light in the sky. ... Dusk is the point when the sun is at 18 degrees below the horizon and there is no longer any sunlight in the sky