Personal jurisdiction refers to a court's authority to make decisions affecting a particular individual or entity based on their connections to the jurisdiction where the court is located. This concept is crucial because it determines whether a court has the right to exercise power over a defendant, which often hinges on factors like the defendant's residency, the location of events related to the case, or whether they have sufficient minimum contacts with the jurisdiction. Understanding personal jurisdiction is essential for grasping how courts establish their authority in legal proceedings.