The Travelers are a technologically advanced race of Humans in the Pegasus galaxy who have escaped being culled by the Wraith by hiding aboard generational ships which travel throughout the Pegasus galaxy.
The Travelers are a spacefaring race of humans who decided to escape the Wraith by launching themselves into space, thereby making it impossible for them to be pinned down in one place. Over the ten-thousand years following the defeat of the Lanteans, they remained aboard their ships, landing as needed for supplies but otherwise keeping on the move. However, without a home base and with virtually no other advanced civilizations in the galaxy, they have been forced to improvise to maintain their fleet. As such, they cannot build new ships, and those that remain are often repaired using mismatched components and haphazard reconstruction.
The Travelers are led by a Governing Council which makes all major decisions pertaining to the race as a whole such as alliances and decisions of war. Individual ship captains, however, make most decisions that apply to their ships individually, such as whether or not to enter a battle. Traveler "law" does not prohibit torture on supposed friendly races. (SGA: "Travelers", "Be All My Sins Remember'd")
Traveler technology is relatively advanced compared to that of most other Pegasus civilizations. They have hyperspace-capable starships, hand-held and ship-mounted energy weapons, and shielding technology. Curiously, Traveler technology is different from most FTL-capable races as it is not based on Control crystals, but on more primitive wires and chips. They are currently the only known civilization that has mastered interstellar travel before mastering crystal or other forms of more "exotic" technologies.
Due to their lack of supplies, Traveler ships are very old and held together with a large amount of juryrigging; most of their scientific resources and efforts are spent maintaining their old and relatively large fleet. Loose wires can seen hanging in most corridors, and Dr. Radek Zelenka has described their hyperdrives as having been assembled from mismatched components (no doubt due the scarcity of necessary replacement parts). They possess a limited understanding of Lantean technology, enough to operate Lantean ships and conduct basic repairs, but lack the Ancient Technology Activation gene.
Travelers wear armbands which serve as a communication device and a radiation sensor. They also have hand-held computers which can be interfaced with other technologies. They make use of spy-satellites with subspace communication abilities to monitor activity in other solar systems. (SGA: "Travelers")
Although once able to build new ships as needed, long term space travel has deprived them of the resources necessary to construct new vessels. Overpopulation and heavy amounts of juryrigging are prevalent. A solution to this problem came when the Travelers discovered an abandoned Lantean Aurora-class battleship. Unable to fly it themselves, they mounted a trap to capture Lt. Colonel John Sheppard, who they knew possessed the Ancient Technology Activation gene necessary to make the technology work. Though Sheppard wasn't cooperative, they eventually engineered an interface using blood samples from him. Sheppard convinced Larrin to let him go, and told her that a spacefaring race such as theirs could one day turn the tide in the battle against the Wraith. (SGA: "Travelers")
When the Asurans began to annihilate human worlds to deprive the Wraith of their food source, Sheppard approached Larrin to enlist her aid in battling their fleet. She presented their plan to the Traveler Governing Council, and several ships were committed to the battle, including their Lantean battleship. The Atlantis expedition made further repairs to the vessel prior to the battle, making it combat-worthy. Though the attack on the Asurans succeeded, one of their generational ships was lost in the battle. (SGA: "Be All My Sins Remember'd")
In 2008, the Travelers decided to establish a permanent settlement on a planet for the first time in generations. Disaster struck when the Attero device was activated, causing the Stargate on that planet to explode when it was activated. Three ships were lost, including their Lantean battleship, and more than 3000 people were killed. Katana Labrea's ship was dispatched to Atlantis to ascertain the cause of the explosion, then aided the Atlantis expedition in the destruction of the device. Her ship defeated two Vanir spaceships in the battle that followed and saved the Daedalus. (SGA: "The Lost Tribe")
It's later revealed that Lieutenant Aiden Ford, believed lost in the Battle of Edowin, was in fact alive and among the Travelers. After Ford had escaped the hive ship he was on during the battle, the Travelers found him on Edowin and took him in. One of their doctors was a former Wraith worshipper and thus knew how to treat Ford's Wraith enzyme withdrawal. With the Travelers help, Ford eventually recovered and took the fight to the Wraith a bit with their help until he was found again by the Atlantis expedition. Afterwards, Ford left the Travelers and returned to Earth with his wife and son. (SGA: "The Third Path")