MACROMEDIA FLASH 8-LEARNING ACTIONSCRIPT 2.0 IN FLASH Manual page 790

Using slash syntax
Slash syntax ( ) was used in Flash 3 and 4 to indicate the target path of a movie clip or
/
variable. In slash syntax, slashes are used instead of dots and variables are preceded
with a colon, as shown in the following example:
myMovieClip/childMovieClip:myVariable
To write the same target path in dot syntax, which is supported by Flash Player 5 and later
versions, use the following syntax:
myMovieClip.childMovieClip.myVariable
Slash syntax was most commonly used with the action, but its use is also no
tellTarget
longer recommended. The action is now preferred because it is more compatible with
with
dot syntax. For more information, see and
tellTarget function with
in the ActionScript 2.0 Language Reference.
statement
790 Writing Scripts for Earlier Versions of Flash Player