The Timeline is the area where we organize and control time based animation in Flash. Flash documents divide lengths of time into frames. In our document, we can set how many frames are shown per second. This is known as the frame rate. When the frames are shown in a sequential order, our brain interprets changes between frames as animation. When an animation has a slow frame rate we are able to see each frame individually and the movement appears choppy. When the frame rate is high our brain can no longer pick out individual frames and the animation looks clean.
Click on each of the example below and see how the different frame rates appear to you. Each animation is 3 seconds long, the only difference is the frame rate.
Animation at 5fps
Animation at 12fps
Animation at 24fps
To give you a reference for what typical frame rates are keep these numbers in mind. The default fps (frames per second) setting in Flash is 12fps. A typical Hollywood movie uses 24fps and TV movies are usually around 30fps. It is not necessary for a Flash document to have a frame rate of 24 or 30 fps since animations are typically used on the Web and a higher frame rate dramatically increases the size of the document. 12 fps gives us a smooth animation without a large file size.
The timeline layout
This is a diagram of the timeline
Click to see an enlarged picture.
Timeline How to guide:
To create a new Keyframe: Select the frame you want to add the Keyframe to. Right Click > Insert Keyframe.
To remove a Frame(s): Select the frames you want to remove. Right Click > Remove frames.
To add a Motion Tween: Select the frames in between two Keyframes. Right Click > Create Motion Tween.
To add a Shape Tween: Left click in-between the two Keyframes where you want to add the Tween. Select: Shape Tween from the Tween option in the properties panel.