The craft skill governs the creation of useful items, materials, and saleable products. All crafters, whatever their eventual specialties, are able to perform basic repair and maintenance (which is very important for weapons and especially armor), as well as create simple, household goods. Craft is a broad discipline, covering perhaps the largest area of any of the skills, and it is mostly defined, for particular characters, by the specialties they take in it. Each level of a particular specialty allows a character to make a range of items, and with increasing levels in a specialty, the most powerful/expensive/useful items become available.
Diplomacy gives a character greater control over their social actions and allows them to influence the world around them. Characters with Diplomacy can censor themselves, act politely in strange situations, and quickly adapt to customs unfamiliar to them. Diplomacy's most far reaching ability, however, is behind-the-scenes influence and manipulation. Specialties in this skill are defined as different areas of influence that characters have (homeworld factions, most commonly). Aggressive use of Diplomacy will almost assuredly result in in-play political entanglements.
The Healing skill, as can be expected, is used to aid the injured and the sick. With a minimal amount of attendence, a healer can stitch up the wounded, preventing them from dying. With more complicated techniques, they can heal a wounded character in very little time. At higher levels, characters can cure infectious diseases and siphon poison from the afflicted. A true master of healing is able to coax a patient back from the very edges of death itself.
Mercantile allows the character to engage in trade and commerce. Characters with Mercantile are skilled in appraising goods, shipping, commerce, and manipulating markets, as well as having an innate sense of buereaucratic processes. Characters can always use this skill to create modest income for themselves during downtime actions. More adventurous characters, however, can engage in market and business speculations. As can be imagined, though speculations can yield great amounts of money, they also carry a real elements of risk. All specialties in this skill involve certain markets, and generally only come into play when speculating in those markets.
Bards, minstrels, dancers, and storytellers are all practicioners of the Performance skill, which can be used to inspire, entertain, and embolden allies. In addition, skilled performers can develop great renown, as their reputations spread far and wide. Performance specialties define exactly which method/instrument a performer employs, as well as which inspiring effects they can use.
This skill governs research, lore, language, and intellectual acumen. Generally, Scholarship is primarily used during downtime actions, allowing a character to gain important information about whatever subject they wish to research. Every even level a character can declare a scholarly specialty, which increases their effective skill level by 2 for purposes of research along those lines. Specialties can also grant a scholar intuitive and immediate knowledge about relevant areas that can be used in play, and may receive GM input about such, if their specialty applies to a situation. Scholarship also allows characters to read and write in languages other than their native tounge and Gatespeak.
Survival is the skill for hunters, trackers, and wilderness folk. It allows characters to find hidden pathways in the wilderness or track down elusive foes. Skilled survivalists can harvest in-game items off the bodies of enemies. Survival specialties allow a character to increase their ability in exploration and tracking, with regards to a specific type of quarry, environment, or condition. True masters of the wilderness learn stealth to such a degree that they can remain hidden almost anywhere.
Tinkering is a broad skill, and it governs the creation, maintenance, and dismantling of machines. It allows characters to create locks, traps, and fantastic devices for various arcane purposes. Though this skill bears some similarity to Craft, Tinkering is fundamentally intellectual and experimental in its pursuit, even if Tinkers are good at such practical matters as trap disarming and lockpicking.