The Key Frame is the foundation of any flash movie. It marks where an event occurs for example, the appearance of a symbol or the end of a motion-tween.
For example, key frame needs to be placed:
The first time you use a symbol in a movie
Any time the appearance of the symbol changes
Look at the example below, and try to follow the same steps in FLASH
In order to create a Key Frame, select the relevant frame and choose
Insert> Insert Keyframe or right click your mouse on the frame for
the same menu. Once you've inserted the key frame a hollow dot will appearing the frame.
Tip:
You can also left click the frame and press the F6 key.
Tip:
When the dot is:
Hollow - it means no symbol is present in that frame.
Solid - it means a symbol is present in that frame.