Harb's duty was to keep morale on the ship high by providing new and different forms of entertainment for off-duty personnel. To this end, Harb utilized a computer system with an advanced (for its time) Artificial Intelligence that he dubbed Moira. Moira helped Harb develop such entertainments as Four-Dimensional Chess, computerized battle simulations, and projecting old two-dimensional holo's for viewing. Dr. McCoy once even utilized Moira to secretly gain access to planetary computers of the Vulcan government.
- The transporter system in the Four-Dimensional Chess was later used to help free the Enterprise from Tafv's forces
- By change the circuitry they were able to beam time-delayed hand weapons using a Tricorder to get the location after a rescue party had given to them.
- Although the artwork and coloring in his comic appearance is roughly done, it seems that Harb is wearing a lieutenant commander or commander insignia of Starfleet rank. He wears yellow divisional patches on his 2285 uniform jacket, despite his department being described by author Diane Duane as a medical or science division (meaning he should have worn green or grey insignia stripes).
- TOS novel: The Wounded Sky
- TOS novel: My Enemy, My Ally
- TOS novel: Spock's World
- TOS novel: Doctor's Orders
- TOS video game: The Kobayashi Alternative
- TOS novel: Swordhunt
- TOS novel: Honor Blade
- TOS novel: The Empty Chair
- TOS novel: Rules of Engagement
- TOS - Double Blind comics: "Double Blind, Part One", "Double Blind, Part II"
- TOS omnibus Rihannsu: The Bloodwing Voyages