What rims should I get?

[jayman4X4]

I'm looking into getting some rims. My question is what is the difference between 15x7 & 15x8. I will be using my explorer off road. I'm running on 30"'s. Thanks

 

[Lifted95X]

The difference between 15X7 and 15X8 is rim width. the 8's are 1 ince wider. If you look at my pics, I have 15X8's on my X.