One of the strengths of Flash is that it facilitates the reuse of objects (such as complex vector shapes) to reduce file size. Objects can be encapsulated, then reused within a document – or even across documents – with a negligible increase in file size. This layer of abstraction reduces load-time when a savvy Flash developer applies them to recurring elements.

These encapsulations are called symbols. Flash defines four kinds of symbol:

  • A graphic symbol consists of any combination of vectors, text, and imported raster images. In the Flash timeline, graphic symbols have just one frame.
  • A button symbol also consists of any combination of vectors, text, and imported raster images. It has four frames in the Flash timeline – three to represent the up, down, and hover states, and a fourth frame to define the area that can be clicked. Respectively, these are known as the up, over, down, and hit states.
  • A movieclip symbol consists of a Flash animation (Matryoshka doll, anyone?). It has its own timeline, and can have any number of frames or layers.
  • A font symbol consists of – you guessed it – a font.

Here’s how you create each. Note that these instructions are for Adobe Flash CS3 for Mac, since that’s what I have.

To create a graphic symbol:

  1. Using the Selection Tool, select the object(s) you want to make into a graphic symbol.
  2. From the menu, choose Modify → Convert to Symbol. Pressing F8, the listed keyboard shortcut, doesn’t work so well here since that’s mapped to Spaces on Mac OS X 10.5+. Maybe some remapping is in order.
  3. Give the symbol a name, and click the Graphic radio button. Press OK.

To create a button symbol:

  1. Using the Selection Tool, select the object(s) you want to make into a graphic symbol.
  2. From the menu, choose Modify → Convert to Symbol.
  3. Give the symbol a name, and click the Button radio button. Press OK.
  4. Double-click the symbol in the Stage. The timeline changes to only have four frames, labeled Up, Over, Down, and Hit. The button’s Up state is now set.
  5. Select the Over frame.
  6. From the menu, choose Insert → Timeline → Keyframe or press F6.
  7. Edit the artwork accordingly to make it reflect the Over state.
  8. If necessary, repeat the above steps (5 – 7) to create the Down and Hit states. If you have no changes to make for the Down and Hit states, you can insert a regular frame (Insert → Timeline → Frame) or press F5.

To create a movieclip symbol:

  1. Using the Selection Tool, select the object(s) you want to make into a movieclip symbol.
  2. From the menu, choose Modify → Convert to Symbol.
  3. Give the symbol a name, and click the Movie clip radio button. Press OK.

To create a font symbol:

  1. In the Library palette, open the Options menu (it’s the wee one with three lines and a down arrow: Picture 1.png). Select New Font.
  2. Enter a name for the font and select the font from the drop-down menu.
  3. If desired, click any of the Bold, Italic, or Bitmap text checkboxes. Enter a Size only if you selected BItmap text.
  4. Click OK.