Same here, I remember when I was learning, before I knew what arrays were I had a bunch of variables like that: $x1, $x2 and I was trying to find a way to convert a number like $n into the variable name so I could do $x$n to reference $x1, $x2. I knew what I was trying to do, just didn't know how to do it correctly at the time because I didn't have any exposure to arrays before.