Abstract: An advertisement distribution server 10 is connected through a communication network N to a user terminal 1 including an application program capable of displaying advertisement information, and distributes the advertisement information to the user terminal 1. The advertisement distribution server 10 includes a CPU 11 and a DB 20 that stores advertisement information 23.

Abstract: An electronic book system, which provides a service for improving usability for users by sharing, acquiring, and analyzing text information and image information contained in an electronic book and various information items added to the electronic book, is provided. A typical aspect of the present invention includes a content server and a terminal including a viewer. The viewer includes comment input means that receives an input of a comment for transmission to the content server and freehand-memo input means that receives an input of a freehand memo for transmission to the content server; and the content server includes a comment processing unit that retains information about the comment in comment storing means, retains information about the freehand memo in freehand-memo storing means, causes the comment and the freehand memo to be displayed when a user browses the electronic book and, when another user browses the electronic book, causes the freehand memo to be displayed on a viewer of the another user.

Abstract: An electronic book system which enables selecting and distributing music matching contents etc. of an electronic book and playing the selected music upon browsing the electronic book. A typical embodiment of the present invention includes a content server and a terminal having a viewer for browsing electronic books and playing music, the viewer including an electronic book playback portion which plays and displays electronic books and a music playback portion which plays music.