Wings Cover Art
The Wings album was released in four different covers (W, I, N, and G versions), and these all fit together to make one larger image of smoke curling around on itself. RM has said that the smoke motif is meant to represent the theme of “temptation” that the Wings album explores.
The albums were designed by Korean branding company VRStudio. You can read a little about their process on their Instagram feed here and here and here. The covers were launched with this branding video:
Member Logos
The circles on the Wings covers are combinations of individual circle logos made for each member.
These individual logos appear at the end of each of the solo MVs made to promote Wings (and sometimes make appearances in the middle of the short films, too). You can watch these MVs here:
This very cool animation was created to show the individual logos linking together.
The individual logos are then combined to create the four circles that appear on the actual album cover.

The four circles are combined into a block shape meant to mimic wings shapes like this.

It’s unofficial, but some ARMY theorists think the four circles represent Broken Promises, Guilt, Sin, and Patience. You can read more detail on this fan theory here.
Each of the individual logos were also released with a tagline which is pretty cool.
More Concepts
VRStudio also published these graphics that, interestingly, show a colour choice for each member, although all Wings branded material is usually in black and white.

Read more in this Twitter Thread from Bangtan Scholars.