I transferred my items media to an external drive, but found that there was a file left on my PC that was full of album artwork. Is there a different function required to move artwork?

I transferred my itunes media folder to an external drive so I could save space on my PC. Some time after I did this, I found a folder still itunes still on my PC.

Inside it had a folder called Album Artwork that was filled with files I could not open, but I assume belong to the songs I had moved. There are also other files in this PC folder that have moblie apps, previous itunes libraries, as well as a few items listed as itunes database files and a bunch of .tmp files.

Did I do something wrong in moving my songs?

I cannot understand why all of this data still exists on my PC when I had moved the media folder to another hard drive.

When I try to get artwork for new songs, they go still to this PC folder. Can anyone offer me any guidance?

Thanks!