Explain the purpose and functionality of masks in After Effects, and provide examples of their applications.

Masks in After Effects serve a crucial purpose in defining and manipulating specific areas of a layer or composition. They act as a non-destructive tool for selecting and isolating regions, allowing users to control the visibility, opacity, and shape of the content within the masked area. Masks offer a range of functionalities and applications, which we will explore in detail: 1. Selective Visibility and Opacity Control: * Masks enable users to selectively control the visibility and opacity of specific areas within a layer. By applying a mask to a layer, users can hide or reveal parts of the content, creating unique visual effects or focusing attention on specific elements. * For example, users can use masks to create a spotlight effect, where only a specific portion of a layer is visible while the rest is masked out. This technique is commonly used to highlight a particular subject or create dramatic lighting effects. 2. Shape Definition and Modification: * Masks provide a versatile tool for defining and modifying the shape of layers and compositions. Users can create masks in various shapes, including rectangles, ellipses, polygons, and custom paths. * The ability to modify mask shapes allows f....