From Wikipedia: Star Wars: X-Wing is the first LucasArts DOS computer game set in the Star Wars universe, as well as the lead title in the X-Wing computer game series. It attempts to "realistically" simulate the experience of combat in the A-wing, X-wing, and Y-wing starfighters of the Rebel Alliance. Fans of the Wing Commander series of games often put forward the mistaken notion that X-Wing was somehow inspired by, or derivative of Wing Commander, but the truth is that X-Wing was built on an evolution of the same game engine that underlay the Air Combat Classics series of World War II flight combat games, (Battlehawks 1942, Their Finest Hour: The Battle of Britain, and Secret Weapons of the Luftwaffe), that were developed by Lawrence Holland for Lucasfilm Games. In fact, Larry Holland has reported that Chris Roberts approached him at a trade show to boast that he had reverse-engineered Battlehawks 1942 to create the Wing Commander game engine which he then attempted to pitch to Lucasarts as the basis for a Star Wars flight combat game! The failure of that pitch led to creation of Wing Commander.

X-Wing's main advance was that it featured a fully 3-D engine instead of bitmaps and sprites. The game also demonstrated a significant step forward in the AI and mission scripting so that players felt immersed in a believable simulation of the Star Wars universe, and faced intelligent adversaries that seemed responsive to the player's tactics. This was in stark contrast to the simple-minded AI of the Wing Commander series that was essentially an arcade shooter for gamers who wanted to experience the fantasy of being a starfighter pilot without requiring anything resembling the necessary skills. X-Wing was a flight combat simulator that required a high level of situational awareness, and some semblance of actual dogfighting skills. The X-Wing series appealed more to "hardcore" gamers and in its original floppy disk version was often found to be too difficult for more casual gamers.