The arrival of a new president brings with it much change. The White House issued 26 Executive Orders on the first day of the new term on a range of topics including immigration, the economy, crime, energy, the environment, and government operations. This rush of presidential actions in just the first week of the new term has many people asking questions: What exactly is an Executive Order, and how does it differ from other presidential actions? What legal authority grants the president powers to issue such orders? What legal weight do Executive Orders and other actions carry? Can they be challenged and how? With the glossary below and links to further reading, we attempt to answer these questions.