Lap Dissolve

 In this type of transition, the first shot ends with a fade out, as simultaneously, the second shot fades in, thus gradually overlapping with the first shot as it fades out. The lap dissolve is thus similar to a fade-out, fade-in, with the main difference being that the middle-sequence of briefly showing a plain-coloured screen is left out so that the end of the first and the beginning of the second shot are briefly superimposed. In continuity editing, lap dissolves are mainly used to flag a temporal discontinuity (i.e. the passage of time).