The Watergate scandal was a serious scandal during and after the 1972 presidential election.
A United States President and Republican, Richard Nixon was running for election against Democrat George McGovern. Afterwards, Frank Wills, a security guard, discovered clues that former FBI and CIA agents broke into the offices of the Democratic Party and George McGovern months before the election. They secretly listened to phone lines and stole several important documents.
When these men were found, they were discovered to have been associated with Nixon. He had helped them cover all the evidence of the scandal, and may have even hired the men to begin with. The Washington Post was a newspaper which played a big role in exposing the misdoings, specifically aided by reporters Bob Woodward and Carl Bernstein. This showed the public that Nixon was not as trustworthy as he seemed.
Nixon chose to resign from office on August 9, 1974 because he wished not to be impeached. This means that he might have been charged with crimes. The U.S. Congress could not impeach him if he resigned. After this, Gerald Ford, his vice-president, became the President by default. Ford pardoned Nixon for all of his crimes later on. The name "Watergate" comes from the hotel in Washington, D.C. where the first crime and break in took place, and is often associated with political scandals.