Portable telephone and program for sending and receiving encrypted electronic mail

摘要

A portable telephone includes a nonvolatile memory, a microcomputer and a liquid crystal panel. The nonvolatile memory stores a plurality of conversion tables employed when an encrypted electronic mail is generated or decrypted. Upon reception of an entry of key information corresponding to any one of the plurality of conversion tables, the microcomputer selects the one conversion table from among the plurality of conversion tables stored in the nonvolatile memory based on the key information. The microcomputer encrypts an electronic mail or decrypts an encrypted electronic mail by referring to the selected conversion table to display the encrypted electronic mail or the decrypted electronic mail on the liquid crystal panel.