CSS3 effects, such as shadows, rounded corners, and opacity, can make web pages more stylish, less harsh, and more welcoming. When used with discretion (that is, not overused), they make web pages attractive and inviting.
Effects and transforms can be, and often should be, combined to produce eye-catching elements. The following text, for example, has both a skew transform and a shadow (box-shadow) effect applied:
Transitions, such as skewing, rotating, scaling, and translation (moving) objects, are particularly engaging when combined with interactivity. For example, a visitor to a website who hovers over an object experiences a subtle but inviting change in it.
In the pre-CSS3 era, these kinds of effects or transitions required some combination coding and embedding Flash objects by relying on (and programming with) JavaScript and substituting images with Photoshop effects for types (for features such as shadows or outlining). These other tools were (are...