15. The non-transitory computer readable storage medium of claim 12 , further including instructions which, when executed by the computer system, cause the computer system to send to the client system for display content of a respective user-selected conversation when the user selects the respective conversation in the displayed first list of conversations.
15. The non-transitory computer readable storage medium of claim 12 , further including instructions which, when executed by the computer system, cause the computer system to send to the client system for display content of a respective user-selected conversation when the user selects the respective conversation in the displayed first list of conversations. 16. The non-transitory computer readable storage medium of claim 15 , including instructions which, when executed by the computer system, enable the user to associate the user-selected conversation with a category while the content of the user-selected conversation is being displayed, the category having a user-specified identifier.