AOS offers a wide range of built-in animation types you can apply to your HTML elements by adding the data-aos attribute. Each animation type creates a different visual effect as the element enters the viewport. Some of the most popular animation types include:

• Fade animations: such as fade, fade-up, fade-down, fade-left, and fade-right;
• Zoom animations: like zoom-in and zoom-out;
• Flip animations: such as flip-left, flip-right, flip-up, and flip-down;
• Slide animations: including slide-up, slide-down, slide-left, and slide-right.

Choosing the right animation depends on your content and the effect you want to achieve. For example, headings often work well with fade or slide animations to draw attention as users scroll. Images can use zoom or flip effects for more dynamic entrances. Buttons and interactive elements may use subtle slides or flips to encourage engagement without being distracting. Always consider the flow of your page and select animations that enhance, rather than overwhelm, your content.