To follow means to go after or behind someone or something. When you follow your teacher down the hallway, you walk behind her. When a detective follows a suspect, he tries to track where that person goes without being noticed.

The word also means to obey or act according to instructions or rules. You might follow directions on a recipe to bake cookies, or follow the rules of a game so everyone plays fairly. When you follow through on a promise, you do what you said you would do.

Following can also mean understanding something as it unfolds. If you're following a complicated story, you understand what's happening even as the plot twists and turns. When you can't make sense of an explanation in math class, you might say, “I'm not following you.”

In another sense, you follow someone when you pay attention to their work or ideas. Scientists follow each other's research to learn about new discoveries. You might follow your favorite author's new books as they come out. On social media, people follow others to see their posts, though this is a recent use of an old word.

People also use follow in phrases like follow your dreams (pursue what matters to you) or follow your instincts (trust your gut feelings about something).