After Effects is a most popular digital visual effects, motion graphics, and compositing software, by Adobe Inc. It is widely used in the film, television, video, and web production industries to create captivating visual effects and dynamic motion graphics.

Key features of Adobe After Effects include:

1. **Compositing**: After Effects allows you to combine multiple visual elements from different sources into a single image or video. You can overlay, blend, and mask various elements to create seamless compositions.

2. **Motion Graphics**: The software enables you to animate text, shapes, and other graphical elements. It offers a wide range of keyframing tools to control the movement and timing of elements.

3. **Visual Effects**: After Effects provides a vast array of effects and presets that can be applied to layers and footage to enhance or alter their appearance. Examples include color correction, distortion, blur, and stylization effects.

4. **Tracking and Stabilization**: You can track the movement of objects or camera footage, which is useful for adding visual effects that follow the motion of the scene. It also includes stabilization features to smooth out shaky footage.

5. **3D Animation**: While not a full-fledged 3D software, After Effects supports basic 3D animation, allowing you to create and manipulate 3D layers and cameras.

6. **Expressions**: After Effects has a powerful expression language that allows you to write scripts to automate tasks, create complex animations, and control properties dynamically.

7. **Masking and Rotoscoping**: You can create masks to isolate specific areas of a layer, making it easy to apply effects or modifications only to those areas. Rotoscoping is the process of manually creating masks to cut out elements from live-action footage.

8. **Integration with Adobe Creative Cloud**: After Effects seamlessly integrates with other Adobe applications like Photoshop, Illustrator, and Premiere Pro, allowing for a smooth workflow between different software.

After Effects is a versatile tool used for various purposes, such as creating motion graphics for titles, intros, and outros, producing special effects for videos, and enhancing footage with visual effects. Its complexity and power make it a popular choice for professional video editors, motion graphic designers, and visual effects artists.