What is the purpose of keyframes in After Effects?

Keyframes in After Effects serve the fundamental purpose of setting the start and end points of an animation, allowing animators to define how a property of a layer changes over time. When you place a keyframe, you are specifying a value for a property at a specific moment in the timeline. By creating multiple keyframes, you can control the transition of that property, such as position, scale, rotation, opacity, and more, making it possible to create smooth animations.

The values between keyframes are automatically interpolated by After Effects, which calculates the changes required to animate smoothly from the value of one keyframe to the next. This interpolation creates a fluid motion effect that enhances the dynamic nature of your animations, making keyframes an essential tool for any After Effects project.

Other functions like creating color effects, adjusting audio levels, or defining layer visibility are specific tasks separate from the core function of keyframes, which is exclusively focused on animation control over time.