Interlace is a technique used in video and image processing that combines two fields of video frames to create a single image. This method helps to reduce flicker and improve the appearance of motion in video playback. It is commonly used in television broadcasting and digital video formats. In interlaced video, each frame is divided into two fields: one containing the odd lines and the other containing the even lines. This approach allows for smoother motion representation, especially in fast-moving scenes. However, it can also lead to artifacts, such as blurring, if not processed correctly, making it less common in modern high-definition formats like progressive scan.