It is enumerated that the advantage of the letter is efficient measures, and remains at other party's hand, and has the means only by mailing, and can send the significant document together even by the one other than digital data because it sends printed matter when it wants to convey feelings firmly.
However, even the other party also costs moderate cost in the person's delivering it, and hangs also days for several weeks in case of foreign countries for several days. Moreover, if it sends it out a lot when addressing it, it becomes very serious work.
It is said that the best advantage of E-mail is fast and easy. It arrives at other party's mail server anywhere all over the world in a few seconds. A peculiar photograph, music, animation, and document to not costing other cost at all, and digital, etc. can be able to be transmitted, and to be transmitted to a lot of other parties all together together.
As the disadvantage, it is not possible to correct, and there are a problem etc. of security when the transmission button is pushed by mistake that when mail can always be seen for the other party if it is not a state of online is not understood.
