GTween is a small but extremely robust library for programmatic tweening, animation, and transitions, built by Grant Skinner of It is currently comprised of 3 key classes:

  • GTween. A robust tweening engine, packed full of innovative features.
  • GTweenTimeline. A powerful virtual timeline that extends GTween to enable you to sequence tweens and actions.
  • GTweener. A static interface to GTween.

It also comes with a variety of plug-ins and easing classes.

Tweening . URL.