Abstract
As we live in the digital society, we can benefit from the Internet and Artificial Intelligence. Then, we have to stare what digital means. Pictures have been digitized, and made into letters. Then, they have been written on paper, and printed as newspapers with printing machines. Furthermore, they have been printed on semiconductors with science and technology. Now, we can share audio, images, and even video as invisible characters on the Internet. This has happened, however feelings are still entrusted in the letters, and they become memories in people’s minds. So, the author hopes that the letters will always be the best gift to make people smile.
