Color grading plugins in After Effects (Ae) are software tools designed to enhance and modify the color and tonal characteristics of video footage. These plugins offer various features such as adjusting exposure, contrast, saturation, and color balance, as well as applying creative effects like color correction and color correction. Popular color grading plugins for Ae include Red Giant's Magic Bullet Suite, DaVinci Resolve's DaVinci Color, and FilmConvert. These tools are essential for professionals in the video editing and post-production industry to achieve the desired visual style and storytelling.