there are a lot of ways you can do that. I'm new to PHP too, and havent heard of the explode(); function. another way you can do it is this:
$var = "1;2;3;4;5";
list($one,$two,$three,$four,$five) = split('[;]', $var);
which is basically the same. the explode() function sounds more efficient in this case, but I'm just trying to offer more perspective.