Boo Hiss WRONG. What they are talking about is merely an attachment at the end of your post like where your rifle photo is. Yeah I know that's a signature but it's only at the bottom of your post below all text.
Using
www.myhostepics.com and getting a URL assigned you can put it anywhere you want in the text and have information about it under or over it. This feature is NOT intended as a replacement for getting URLs assigned to your photos it's just an added feature.
In cases like recently when we switched to the new server ALL those images so loaded prior to that are now history. But any that were assigned a URL and added properly are still there. Who knows when some other change here will once again invalidate any attachment images. Avatars were also affected and many now are dead links. I'm removing the dead ones as I find them and if folks want an avatar they'll need to reload it.