"Players of the original game are never told the hero's name, but are instead asked to enter their own. The default name of "Roger Wilco" — a reference to the abbreviated radio communication, "Roger, Will Comply" — became the de facto name of the hero in the later games of the series.
Roger is a member of the cleaning crew onboard the scientific spaceship "Arcada", which holds a powerful experimental device called the "Star Generator" (a thinly-veiled reference to the Genesis Device from Star Trek II). Roger emerges from an on-duty nap in a broom closet to find that the ship has been boarded and seized by the sinister Sariens. Using a keycard that he found from the body of a fellow fallen crew member named Jerry, he finds his way to an escape pod and escapes the "Arcada". After crash-landing, he finds himself on a dry and barren wasteland that is the planet Kerona. Making his way through the desert and through a system of caves below, he is tasked with the killing of a creature called the Orat. He finds the Orat in a cave, and duly kills it..."
Source: Wikipedia, "Space_Quest:_The_Sarien_Encounter," available under the CC-BY-SA License.