Interlacing is a technique used to improve the picture quality of a video transmission without consuming any extra bandwidth. While interlace can improve the resolution of still images, it can cause flicker and various kinds of distortion.
Most consumer camcorders record interlaced video, though progressive frame video cameras are becoming more popular. Interlace is still used for most standard television broadcasts, though videos destined for the computer viewing should be de-interlaced.

