The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite systems (GNSS) that provides geolocation and time information to a GPS receiver anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. Obstacles such as mountains and buildings can block the relatively weak GPS signals.

The GPS does not require the user to transmit any data, and it operates independently of any telephonic or Internet reception, though these technologies can enhance the usefulness of the GPS positioning information. The GPS provides critical positioning capabilities to military, civil, and commercial users around the world. The United States government created the system, maintains and controls it, and makes it freely accessible to anyone with a GPS receiver.The GPS project was started by the U.S. Department of Defense in 1973. The first prototype spacecraft was launched in 1978 and the full constellation of 24 satellites became operational in 1993. Originally limited to use by the United States military, civilian use was allowed from the 1980s following an executive order from President Ronald Reagan after the Korean Air Lines Flight 007 incident. Advances in technology and new demands on the existing system have now led to efforts to modernize the GPS and implement the next generation of GPS Block IIIA satellites and Next Generation Operational Control System (OCX). Announcements from Vice President Al Gore and the Clinton Administration in 1998 initiated these changes, which were authorized by the U.S. Congress in 2000.

During the 1990s, GPS quality was degraded by the United States government in a program called Selective Availability; this was discontinued on May 1, 2000, in accordance with a law signed by President Bill Clinton.The GPS service is controlled by the United States government, which can selectively deny access to the system, as happened to the Indian military in 1999 during the Kargil War, or degrade the service at any time. As a result, several countries have developed or are in the process of setting up other global or regional satellite navigation systems. The Russian Global Navigation Satellite System (GLONASS) was developed contemporaneously with GPS, but suffered from incomplete coverage of the globe until the mid-2000s. GLONASS can be added to GPS devices, making more satellites available and enabling positions to be fixed more quickly and accurately, to within two meters (6.6 ft). China's BeiDou Navigation Satellite System began global services in 2018, and finished its full deployment in 2020.

There are also the European Union Galileo navigation satellite system, and India's NavIC. Japan's Quasi-Zenith Satellite System (QZSS) is a GPS satellite-based augmentation system to enhance GPS's accuracy in Asia-Oceania, with satellite navigation independent of GPS scheduled for 2023.When selective availability was lifted in 2000, GPS had about a five-meter (16 ft) accuracy. GPS receivers that use the L5 band can have much higher accuracy, pinpointing to within 30 centimeters (11.8 in), while high-end users (typically engineering and land surveying applications) are able to have accuracy on several of the bandwidth signals to within two centimeters, and even sub-millimeter accuracy for long-term measurements. Consumer devices, like smartphones, can be as accurate as to within 4.9 m (or better with assistive services like Wi-Fi positioning also enabled). As of May 2021, 16 GPS satellites are broadcasting L5 signals, and the signals are considered pre-operational, scheduled to reach 24 satellites by approximately 2027.

William Jefferson Clinton (né Blythe III; born August 19, 1946) is an American politician who served as the 42nd president of the United States from 1993 to 2001. He previously served as governor of Arkansas from 1979 to 1981 and again from 1983 to 1992, and as attorney general of Arkansas from 1977 to 1979. A member of the Democratic Party, Clinton became known as a New Democrat, as many of his policies reflected a centrist "Third Way" political philosophy. He is the husband of Hillary Clinton, who was a senator from New York from 2001 to 2009, secretary of state from 2009 to 2013 and the Democratic nominee for president in the 2016 presidential election.

Clinton was born and raised in Arkansas and attended Georgetown University. He received a Rhodes Scholarship to study at University College, Oxford, and he later graduated from Yale Law School. He met Hillary Rodham at Yale; they married in 1975. After graduating from law school, Clinton returned to Arkansas and won election as state attorney general, followed by two non-consecutive terms as Arkansas governor. As governor, he overhauled the state's education system and served as chairman of the National Governors Association. Clinton was elected president in the 1992 presidential election, defeating incumbent Republican president George H. W. Bush and independent businessman Ross Perot. At 46 years old, he became the third-youngest president of the United States.

Clinton presided over the longest period of peacetime economic expansion in American history. He signed into law the North American Free Trade Agreement (NAFTA) and the Violent Crime Control and Law Enforcement Act, but failed to pass his plan for national health care reform. In the 1994 elections, the Republican Party won unified control of Congress for the first time in 40 years, however, Clinton was reelected in the 1996 with a landslide victory. Starting in the mid 1990s, he began an ideological evolution as he became much more conservative in his domestic policy advocating for welfare reform and the State Children's Health Insurance Program, as well as financial deregulation measures. He also appointed Ruth Bader Ginsburg and Stephen Breyer to the U.S. Supreme Court. During the last three years of Clinton's presidency, the Congressional Budget Office reported a budget surplus—the first such surplus since 1969. In foreign policy, Clinton ordered U.S. military intervention in the Bosnian and Kosovo wars, signed the Dayton Peace agreement. He also called for the expansion of NATO in Eastern Europe and many former Warsaw Pact members joined NATO during his presidency. Clinton's foreign policy in the Middle East saw him sign the Iraq Liberation Act which gave aid to groups against Saddam Hussein. He also participated in the Oslo I Accord and Camp David Summit to advance the Israeli–Palestinian peace process, and assisted the Northern Ireland peace process.

Clinton's second term would be dominated by the Monica Lewinsky scandal which began in 1996, when he began a sexual affair with 22-year-old White House intern Monica Lewinsky. In January 1998, news of the sexual relationship made tabloid headlines. The scandal escalated throughout the year, culminating on December 19 when Clinton was impeached by the House of Representatives, becoming the second U.S. president to be impeached after Andrew Johnson. The two impeachment articles that the House passed were centered around Clinton using the powers of the presidency to obstruct the investigation and that he lied under oath. In 1999 Clinton's impeachment trial begin in the Senate. Clinton was acquitted on both charges as the Senate failed to cast 67 votes against him, the conviction threshold.

Clinton left office in 2001 with the highest end-of-term approval rating of any U.S. president since Franklin D. Roosevelt. His presidency has been ranked among the upper tier in historical rankings of U.S. presidents. However, his personal conduct and allegations of sexual assault against him have made him the subject of substantial scrutiny. Since leaving office, he has been involved in public speaking and humanitarian work. He created the Clinton Foundation to address international causes such as the prevention of HIV/AIDS and global warming. In 2009, he was named the United Nations Special Envoy to Haiti. After the 2010 Haiti earthquake, Clinton and George W. Bush formed the Clinton Bush Haiti Fund. He has remained active in Democratic Party politics, campaigning for his wife's 2008 and 2016 presidential campaigns.