In this chapter we briefly review the history of X-ray Astronomy through its missions. We follow a temporal development, from the first instruments onboard rockets and balloons to the most recent and complex space missions. We intend to provide the reader with detailed information and references on the many missions and instruments that have contributed to the success of the exploration of the Xray Universe. We have not included missions that are still operating, providing the world-wide community with high quality observations. Specific chapters for these missions are included in a dedicated section of the handbook.