Turns keyframing mode on or off.
All animatable transformations and modifications are keyframed while the Animate button is on. When it's off, modifications are applied to frame 0.
Keyboard shortcut to toggle the Animate button: n
For example, if you have a cylinder that has not been animated yet, it has no keys. If you turn on the Animate button, and on frame 20 you rotate the cylinder 90 degrees about its Y axis, Rotate keys are created at frames 0 and 20. The key at frame 0 stores the original orientation of the cylinder, while the key at frame 20 stores the animated rotation of 90 degrees. When you play the animation, the cylinder rotates 90 degrees about its Y axis over 20 frames.
The Animate button and the highlight border around the active viewport both turn red.
A Move key is created at frames 0 and 25. The establishing key at frame 0 describes the object's position at point A. The key at frame 25 describes the object's position at frame 25.
A Move key is created at frame 50 that describes the object's position at point C.
You can't animate the number of boxes in the ring.
The interactive method of IK animation is best suited for expressive character animation or animations where the exact placement of objects is restricted to a few keyframes.