What is the difference between split() and explode()?

[tarm]

The PHP manual for \[code\]split()\[/code\] says\[quote\] This function has been DEPRECATED as of PHP 5.3.0. Relying on this feature is highly discouraged...Use \[code\]explode()\[/code\] instead.\[/quote\]But I can't find a difference between \[code\]split()\[/code\] and \[code\]explode()\[/code\]. \[code\]join()\[/code\] hasn't been deprecated, so what gives?