With the development of the internet,more and more people send cards of different kinds with E-mail on the internet.Comparing with the traditional cards,the digital cards are much more interesting and lively.There can be some pictures,cartoons,flashes and different sounds.Meanwhile,the cards on the internet can be transmitted at a very high speed.With different addresses.you can send different cards.Suppose you are not interested in cards,you can also design the style of your own with certain software.With the popularity of the digital cards on the internet,we can get rid of the traditional cards which are made of paper.In this way, we can save lots of wood.It should be regarded as a contribution to the preservation of the environment.