This report describes the development of computer programs called user agents, which, through interaction with users, can either learn new facts and store them in a data base or learn new procedures for data manipulation and represent them as programs. These programs are written in RITA, the Rule-directed Interactive Transaction Agent system, and are organized as sets of IF-THEN rules or "production systems." The programs are able to act as "personal computer agents" to perform a variety of tasks. Four types of RITA agents are (1) an exemplary programing agent that watches a user perform an arbitrary series of operations on the computer and then writes a program (a new RITA agent) to perform the same task; (2) a self-modifying agent that performs ARPAnet file-transfer tasks for the user, modifying itself so that each subsequent time it performs the task, it can do so with less help from the user; (3) a tutoring agent that watches an expert demonstrate the use of an interactive computer language or local operating system and then creates a teaching agent that can help naive users become familiar with the language or system demonstrated by the expert; and (4) a reactive-message creating agent that elicits text from a user (the sender) and uses it to create a new RITA agent which is a reactive message; the reactive message is then sent to some other user (the recipient), who interacts with it; and during the course of the interaction, a record of the recipient's responses is sent back to the sender. (Author/CMV)