Animation in Flash:
Launch Flash. Become familiar with the set up. Key elements:
Stage: where you animate your project.
Graphic symbol: basic symbol.
Movie symbol: privileged symbol, perfect for advanced scripting.
Frame: frames on the timeline crucial for an animation.
Keyframe: needed to create animation shifts throughout the timeline.
Timeline: where you create your animation.
Layers: where you place your symbols to be animated.

To animate:
Open a flash project, locate the stage. Select a layer and create a graphic with the tools available on Top Menu > Window > Tools. These are similar to Illustrators. Experiment.

Once you have an object that you want to animate, select it, then on the top menu select: Modify > Convert to Symbol, choose movie symbol.

To import a file go to the top menu: File > Import, then choose "Import to stage" or "Import to library."

Note: all symbols are stored in your library. What you see on the stage is an instance of your symbol. You can have as many duplicates of your symbol as you like.

To animate your symbol, select a layer, then place your symbol on the stage. On the Layer palette, at the top, select a frame according to how long you want your animation to be. Then, on the top menu select: Insert > Timeline > Keyframe. Move your object in the last key frame to wherever you want. (note: you will only be able to move object in keyframes, not on regular frames.) Create as many keyframes to move your object around as desired.

Repeat this for as many layers as you like. Note that you can only have one object per layer if you are going to animate the object, but you may have as many objects in one layer if the objects are static.