Flash can create two types of tweened animation using timeline:

Creation of Motion/Shape tween using timeline is the basics of Flash.




By tweening shapes, you can create an effect similar to morphing, making one shape appear to change into another shape over time. Flash can also tween the location, size, and color of shapes.

This tutorial will teach you a simple shape tween.

Steps to follow:

• Open a new flash file (Ctrl+N).
  New Document window will appear
  Select General panel and choose Type: Flash Document . Press OK.
• If your timeline window is not open, press (Ctrl+Alt+T).
• Now you can see a single Layer called "Layer1" in your timeline Window.
  
  
• Select the first frame. Now go to your working area and draw any object. To start off with, may be you can draw a circle.This is going to be your initial object.
  In the above demonstration, my initial object is a short line.
• Select frame 20 and press F6 to insert a new keyframe.
• Still keeping playhead on frame 20, delete the object present in your working area. Now draw a different object, may be a square.
  In the above demonstration, I have drawn a long line.
• Select any frame between, 2 to 19 and select Shape from the tween pop-up menu in the Property inspector. Now your Layer will look something like the one shown below.
  
  
• Now press (Ctrl+Enter) to view your motion tween.

In the above tutorial, you learnt how to create a simple shape tween. Believe me, using this logic you can create n number of beautiful things. Here is a simple example just to trigger your creativity.