Final answer:
The aesthetic function that can make an element 'slide' onto the page is animation.
Step-by-step explanation:
Slide-In Animation
The aesthetic function that can be used to make an element 'slide' onto the page is animation. Using CSS animation properties and keyframes, you can create a slide-in effect for an element. For example, you can use the animation-name property to specify a slide-in animation and the animation-duration property to control the speed of the animation. By applying these CSS properties to an element, you can achieve the desired slide-in effect.