Animation easing determines how an animation accelerates or decelerates as it plays, shaping the overall feel of the movement. With AOS, you can customize easing by adding the data-aos-easing attribute to any animated element. This attribute accepts standard timing functions such as "linear", "ease-in", "ease-out", "ease-in-out", or even custom "cubic-bezier" values for advanced control.

Choosing the right easing is important for user experience:

• Linear easing results in a steady, mechanical motion;
• Ease-in starts slowly and speeds up, making elements feel like they are gaining momentum;
• Ease-out starts quickly and slows down, which is useful for gentle landings;
• Ease-in-out combines both for a natural, smooth effect;
• Custom cubic-bezier curves let you fine-tune the motion for unique or branded interactions.

When customizing animation easing, consider the mood and intent of your interface. For playful or dramatic effects, experiment with custom cubic-bezier values. For subtle, professional transitions, stick with standard easings like "ease-in-out". Always preview your animations on real devices to ensure they feel right and do not distract from your content.