The forces of good and evil are very clearly defined in the film. The story's positive messages include hard work and perseverance paying off with results, the power of personal sacrifice in pursuit of a larger good, and accepting those who are different or difficult to get along with. Additional themes include courage, self-control, and teamwork.
Much of the film's banter is based in mildly antagonistic relationships between characters, so there are frequent insults and one-liners bandied back and forth. Otherwise, there are a few instances of "damn" and "hell."
No real-world brands or products are featured in the film, since it takes place in another galaxy. But the movie created a template for movie merchandising that persists to this day. Decades after release, its characters are still immortalized in action figures, video games, and countless other products.
Characters visit an intergalactic cantina where otherworldly beverages are served and strange substances are smoked. But it has no visible parallel to anything available in reality.