For the research and development of a new multi-medium like digital library and digital museum, there is a great deal of concern from communication theories and the nature of digital medium. Besides of the theory of "transmission model," other theories like "communication as culture," "diffusion of innovations," and "new media technology" should be taken into account seriously and thoroughly. Other related issues such as "information inequality/gap," "information searching/referencing on the Internet," virtual reading community," "users as creators of content," "human interface," and "access to the general public" are also key factors of a successful digital library and digital museum in the information age.