Destiny
Destiny is a big part of the story. Doc and Marty realize that also the small parts that are changed in the story can have a big impact on how the future unfolds. Therefore, it is not only a person and their own decision that determine how successful or happy they become; it is the people around and destiny itself.
Intensions and goals
Each of the characters in Back to the Future have goals. They are planning on becoming something as they grow up, either it is becoming a writer or building a time machine. Managing to go the places you hoped you would go, as well as not giving up when facing obstacles are important factors that built the main characters throughout the story.
Family
Marty’s family is always in the center of the shot. When Marty time travels, he still stays close to his family, making sure that everything that happens with them works out and trying to make sure they will be blessed by his time travel. Family is one of the main themes, as that is essentially what the story is about. When breaking down the exterior factors; dilemmas and time-travel and other problems, the only thing that remains is Marty’s love for his family.
