strange arrow showing on sub-folders after moving from the main one

I put all my desktop located files into ONE folder.
Then I needed quicker access to some of the folders so I moved them back to my desktop.
Now they all have a little arrow in the bottom left corner.
Why is this?
Is it important?
When I put them into the one main folder they retain the little arrow which is different to the triangle that allows access to the folder contents in list view though seems to have the same function once in the main folder. They don't have that triangle any more.
it is a curly arrow rather than a little triangle.

If there was a way to upload screen shots I am sure you would understand properly what I am trying to say.

At first this used to be on just one sub folder now it is on many of them.

Thanks for any insight on this
Shirley