PORTABLE INFORMATION APPARATUS, SERVER, ELECTRONIC BOOK, PROGRAM AND INFORMATION STORAGE MEDIUM

PROBLEM TO BE SOLVED: To provide an electronic book, a portable information apparatus and an information storage medium used for them capable of realizing functions such as rotation, expansion, shrinkage, and scroll of a map image via a user-friendly human interface.SOLUTION: An electronic book comprises a display part capable of displaying a map image. According to an operation history of a finger brought into contact with the display part, an execution instruction and an operation amount for at least one operation among rotation, expansion, shrinkage, and scroll of the map image can be inputted at the same time. By motion to separate the two fingers from each other, an expansion instruction and an expansion amount of the map image can be inputted. By motion to bring two fingers close to each other, a shrinkage instruction and a shrinkage amount of the map image can be inputted. By motion to turn one finger using another finger as an axis, a rotation instruction and a rotation amount of the map image can be inputted.