Wait—you don't know who John Williams is? Holy smokes! Even though you might not know him by name, you definitely know Mr. Williams by his work.

Ever seen Jaws? Jurassic Park? Harry Potter? Indiana Jones?

If you have, then you've heard some of Williams' music, which means that you've almost definitely absent-mindedly hummed a few tunes while in the shower.

Basically, Williams is one of the most well-known film composers of all-time. His music is deeply melodic and emotional, which makes it the perfect pepper for the steak of a good movie. What's more, he ends up defining the films he works on through his scores.

This is achieved primarily through his use of the "leitmotif" technique, which was made famous by composer Richard Wagner. Basically, a "leitmotif" is a musical phrase that is used when a specific characters enters the scene in a film or play, which, over time, associates that specific musical phrase with that specific character. The opening scene is a great example of this: Both Han and Luke's entrances are signaled by their respective themes. These "leitmotifs" can change and blend over time, which can be used to illustrate changes to characters.

For example, The Empire Strikes Back marks the first appearance of perhaps the most famous leitmotif in the series: Darth Vader's Imperial March. This theme gets played at full-blast the moment that Darth Vader appears, signaling that the threat that had only been a whisper at the beginning of the film has now grown into a roar.

Just contrast that with Yoda's theme, or with Han and Leia's love theme, for that matter. It's pretty easy to tell the good guys from the bad. By creating a dense system of interlocking musical compositions, Williams doesn't just create cool tunes to play in the background of battle scenes—he ends up defining the Star Wars series as much as any actor, director, or writer who played a part in its creation. Yeah, we're talking to you too, Lucas.