Easy RegExp Trivia

[Charter]

Here's an easy one... In words, describe what the following does:

$foo = eregi_replace("([a-z0-9])[/]+","\\\\1/",$foo);

[druesome]

I'm guessing it converts any alphanumeric character followed by a slash in $foo into the characters \1/ then spits out $foo? Just a wild guess from a newbie.:p