the terminal device acquires the content of the line from the window 24 when the user clicks this conversation the terminal devices recognizes the portion between u201c lt u201d and u201c u201d as the channel name and changes the channel being noticed to this channel the terminal device has a correspondence table of each line of window 24 of other channel and speaking channels provided in the memory device this correspondence table is updated as follows 2 the message is displayed in the unit of one line in the window 24 of other channel 3 when displaying the message in the window 24 of other channel the channel name is added to the end of the correspondence table 4 as a result of 1 2 3 the channel name corresponding to the message in each line is stored in the correspondence table when the user double clicks the window 24 of other channel the terminal device acquires the double clicked line line number from the window 24 searching the correspondence table by using the line number the channel name corresponding to the line number is acquired the acquired channel number is the channel being noticed 0092 fig5 is an explanatory diagram showing the display screen of.