In digital camera
terminology the active child mode
is a type of scene mode photographers can use to produce the best results when photographing moving subjects, such as active children. The active child mode lets you frame and select the child before you begin shooting the pictures. Once framed the camera will then track and focus on that moving subject enabling you to shoot faster with clearer images as a result. Active child mode is a shooting mode found on many Nikon brand digital cameras and may also be an option when capturing motion picture recording (videos) using the camera, rather than still pictures.
See also “Digital Cameras” in the Quick Reference section of Webopedia.