This skill is covered in the Explorer's Edition. In a sci-fi setting, characters have areas of expertise not listed in the book. This section helps the GM consider other skill areas specific to his setting. This is a general category that covers anything you can imagine your character has knowledge in. For instance, you character might have knowledge in specific sciences like astrobiology, local customs of Ken'zah Kit or how to plot navigational paths between star systems. Here are some examples how to record these types of skills on your character sheet.

Knowledge:Astrobiology d6
Knowledge:Astrogation d8
Knowledge:Ken'zah Kit, Customs and Politics d6

Technology is everywhere in the frontier. It is assumed if the character grew up on a modern world they would know how to use a computer, drive a hovercar and give a robot commands. Beyond the basics, your character must be skilled to repair these types of devices. The following is a guideline when repairing or working on computers, robotics, demolitions, machines, gadgets, vehicles, weapons, locks, sensors, detection equipment etc. 

Each time your character attempts to repair something he must have the tools and materials neccessary to complete the job. A tech-kit has all the neccessary items to make field repairs on almost any device in the frontier. Each time the tech-kit is used, provision points are depleted. When the points reach zero the tech-kit is nothing more than a case to hold tools. 

Sometimes however the repair may only be made in a properly stocked shop. Your GM will know if that's the case. 

The doors of 43 East Summit street are equipment with high-tech biometric scanners. A technician can thwart the locks using his tech-kit by expending 4 provision points and rolling a 6 or better on his skill check. If he fails the points are still depleted from the kit.

Toerne is working on a robot for his next excrusion into the Unsettled Lands. Since he'll be far away from a parts shop he needs something that can easily be fixed in the field. He asks his GM if he can swap out the high-tech inards for modern-tech. The GM states he does not have those types of parts in his tech-kit but my purchase the parts for 400 credits. No roll is neccessary since Toerne is not in a combat situion and has all the time in the world to fix. If he's stummped he can simple seach GalactipediaNET for some help. 

Sothedol and his crew are attempting to outrun piriates in a densly packed asteroid field. He makes a Repair roll to tweak the high-tech thrusters hoping to give them a 20% boosts. 

Devices of alien origin are penalized -2 to use. Repair is -4.