You can say that PAMM account is a profit-sharing account in this account you invest your money with many other traders in this way your account have big capital and you start trading with this big capital and as you earn some money from it you divide this profit among all shareholders of the capital. This account is used for big investors and professional traders. While the signal buying services are totally different these kinds of services just provide you the signals which can give you profit or loss. Here the company does not share with you in loss and profit and also they can not give you an idea of money management.