While the sides in Star Wars are generally broken up rather simply to Light and Dark sides of the force, like everything in life, it's not really that simple. There's the 3rd "faction" to deal with. They're the smugglers, the bounty hunters, the thieves, and many others just looking to get by any way they can. Sure, they might lean towards "good" or "bad," but they're their own. In Star Wars: Destiny, they also get their own color of card: yellow.
As you'd expect from a group that's rather diverse as smugglers and such can be, the yellow cards in the game have a wide range of abilities. Perhaps you want to head to a different battlefield. Or maybe you found an ability on another card you'd like to have use of. Or maybe you just want to play Han Solo and get a whole bunch of actions in a row because he's cool like that. You certainly have plenty of options here.