An obligation is something you're required to do because of a promise, rule, duty, or sense of what's right. If you borrow your friend's bike, you have an obligation to return it in good condition. If you promise to help your sister with her project, you've created an obligation to follow through.

Obligations come from different sources. Some are legal: citizens have an obligation to obey laws. Some come from agreements: when you join a soccer team, you take on obligations to attend practices and support your teammates. Others come from relationships: parents have obligations to care for their children.

The word carries weight because obligations matter whether you feel like doing them or not. You might not want to finish your homework, but you still have an obligation to complete it. A business owner might prefer to spend money elsewhere, but they still have obligations to pay employees and suppliers.

People sometimes confuse obligations with things they merely should do. An obligation is stronger: it's something others are counting on you to do, or something you've genuinely committed to doing.