Lesson: Types of Conflict
In any story there is conflict. If there is not then it's not much of a story. Depending on the source you will generally find three types of conflict:
1. Person vs. Person 
This is where you have two people a Protagonist (main character, generally the hero of the story) and the Antagonist (the person working against the protagonist, generally the villain.) Any time you have a misunderstanding between people, it's this type of conflict.
2. Person vs. Environment 
This kind of conflict happens when things just don't ever seem to work out right for someone. Circumstances always seem to be against the protagonist. In some cases, the person may be quite literally in conflict with the environment in the case of a film like Twister (it's terrible, don't watch it.)
3. Person vs. Self 
This typ of conflict is that wonderful type of story where we see people learn a lesson and grow at the end. Their own actions and thoughts are literally keeping them from happiness and through the course of the story some revelation happens that teaches the person how to be a better human. Or, in the case of one film (I don't want to ruin it for you) the person might literally fight against himself.
Think of all of the types of conflict you've had in your life. Can you categorize them? Here's one to consider, what category would a film like Terminator fit into when the antagonist is a robot? When you can defend your answer, you've understood conflict and are ready to move on.