You have found a trap. Now you are trying to figure out how it works.

The DC to discern the trap is using the Trap DC.

If Successful:

1. You will discover its trigger, or how it activates, and any relevant enchantment if it does go off.
2. You also find out the Trap DC to disarm the trap.

If Unsuccessful:

1. If you fail discerning the trap by DC by 7 or more, the trap is triggered.
2. Otherwise you can attempt to repeat as many times as needed to study and discern the trap's working.

Skills to Discern the Trap:

1. The Innate Skill of Inspection can be used to try to discern a trap's function. Since this isn't a specialized roll, the DC to find out to discern is increased by by +5. This skill is automatically used if the creature is untrained in Machining and Magic.
2. Mechanical Traps, which is a the default trap type, use Machining to Discern how it is being used.
3. If you successfully Discern the Trap, you can try to Disarm the Trap using Machining. If the trap is disarmed, and no longer Trapped, you can try to gather the parts of the trap using Dismantle. Each trap component might have a DC of its own. After each component is disarmed, you may retrieve the final trap piece.
4. Magical Traps, which use innate spells, at will spells, or charged spells are considered a Magical Trap. If you have at least 1 skill point in Magic, you use Magic to discern how the trap works.
5. If you successfully Discern the trap, you can try to Disarm the trap using Magic. If the trap is successfully disarmed, you can try to Disenchanting Inventory for dust, if it meets the requirements using Enchanting. Each trap component might have a DC of its own. After each component is disarmed, you may retrieve the final trap piece.
6. Even if you fail to discern the trap, or don't want to discern the trap, as long as the trap is not hidden, you can still attempt to disarm it using either Machining, or Magic. The type of trap is still revealed if not Hidden; you can see the magical runes, gears, or so forth.