Different in nature. Drainage video is drained to the live broadcast room through short video to improve the admission rate of the live broadcast room. The preheating video is a live broadcast preview, telling the audience the live broadcast time and benefits. This is a live warm-up video. Video tidbits are clips in the process of video shooting. Now, in order to promote the promotional film, some clips will be condensed into a few minutes of tidbits for publicity.