Ran is the past tense of the verb run. When you say “I ran to school this morning,” you're describing running that already happened.

Running means moving faster than walking by pushing off with your legs so that both feet leave the ground with each stride. Yesterday you ran, but today you run. If you've been running regularly, you might say “I have run every day this week.”

The word also applies to how things operate or function. A battery that ran out of power has stopped working. A movie that ran for two hours lasted that long. A candidate who ran for class president competed in the election. A manager who ran the school store was in charge of it.

You'll also hear ran in phrases like “the car ran out of gas” (it used up all its fuel) or “the meeting ran late” (it lasted longer than planned). In each case, ran is describing an action or state that happened in the past.