Training collars for dogs?

I would never use a shock collar on my dog I was at a store looking at training collars one said it dosnt hurt the dog you press a botton and it sends a annoying simulation to the dog isnt this fancy words for shock collar? Can someone explaine the difference between shock and stimulation collars? Also the one I was looking for I thought they had one where you press a botton and it just sends a loud noise they dont like but dosnt shock them does anyone know anything about these? My main use is that he dosnt listen to me when I give him a comand and hes not close by me I thought if I told him no or to drop something and he didnt I could use the noise to get his attention and get him to stop.