President of the United States(End)

Secret Service
The United States Secret Service is charged with protecting the sitting president and his family. Until 1997, all former presidents and their families were protected by the Secret Service until the president's death. The last president to have lifetime Secret Service protection is Bill Clinton; George W. Bush and all subsequent presidents will be protected by the Secret Service for a maximum of ten years after leaving office.[17] However, debates in Congress have been raised concerning this decision. Following the increase in terrorism and threats to the president in general since 1997, lifetime protection is being reconsidered.
Presidential libraries
Main article: Presidential library
Each president since Herbert Hoover has created a repository known as a presidential library for preserving and making available their papers, records, and other documents and materials. Completed libraries are deeded to and maintained by the National Archives and Records Administration (NARA); the initial funding for building and equipping each library must come from private, non-federal sources. There are currently twelve presidential libraries in the NARA system. There are also a number of presidential libraries maintained by state governments and private foundations, such as the Abraham Lincoln Presidential Library and Museum, which is run by the State of Illinois.

After the presidency
Some presidents have had significant careers after leaving office. Prominent examples include William Howard Taft's tenure as Chief Justice of the Supreme Court and Herbert Hoover's work on government reorganization after World War II. More recently, Jimmy Carter has become a global human rights campaigner, international arbiter and election monitor, and a recipient of the Nobel Peace Prize. Other former presidents have served in elected office after leaving the White House; Andrew Johnson was elected to the Senate after his term was over, and John Quincy Adams served in the House of Representatives for eighteen years. Grover Cleveland, whose bid for reelection failed in 1888, was elected president again four years later in 1892. John Tyler served in the provisional Confederate States Congress during the Civil War, and was elected to the official Confederate Congress, but died before it convened.
Source : http://en.wikipedia.org/wiki/President_of_the_United_States