What is the difference between GPS and EGNOS?

GPS is a global navigation satellite system (GNSS) that allows anyone with a GPS receiver to navigate from anywhere in the world. EGNOS is a satellite-based augmentation system (SBAS) that makes the GPS signal more precise. EGNOS also provides an integrity signal about GPS performance by broadcasting error corrections to the users in Europe via three geostationary satellites. This means that without a GPS signal, EGNOS will not work.