Scavenging has a deep and rich history in the Star Wars universe, be it a Jawa, an Ugnaught, a Toydarian, or basically any other race under four feet tall. Everybody loves picking up junk and turning into more, slightly different junk. Even Darth Vader does it.
And in The Old Republic it’s not much different. Come across a dead droid, a crashed speeder, or some other piece of deleterious and turn it into parts.
Quests are also available to pick up materials, which is especially helpful if you’re missing some higher end mats. The materials you collect from scavenging can be used to make parts for Armstech, Armormech, and Cybertech as well as selling on the Galactic Trade Network.
One character should be enough to keep you steeped in Scavenging mats, as they tend to come fairly quickly and in large numbers as you progress through the game. This is especially true as any droid you encounter of tough status or above can be scanned and scuttled for parts.