We pause to remember the events of that tragic day, as well as honor the victims and the heroism of first responders.

Here are some of the lesser-known African American women scientists who have made groundbreaking impacts in their respective fields.

Real-life heroes Spencer Stone, Alek Skarlatos, and Anthony Sadler portray themselves in 'The 15:17 to Paris,' Clint Eastwood's retelling of how they incapacitated a crazed gunman and saved closed to 600 lives on board a train in August 2015.

The home-grown terrorist responded to a Harvard reunion query by calling his current occupation as 'prisoner' and his eight life sentences as 'awards.'

The much-anticipated second season of 'American Crime Story' examines the events leading up to Versace's death and explores the cultural context of his murder, including the homophobic climate of the 1990s.

Here's a primer on the true-crime case of brothers Lyle and Erik Menendez who were sentenced to life in prison for murdering their parents in 1989.

A look back at the victims of the Salem Witch Trials and the mass hysteria that led to their deaths.

David Berkowitz, who became known as Son of Sam, went on a murderous rampage in New York City during the 1970s, taunting and insulting police, until they captured him. Here's a look back at his notorious case.

The 1848 historic event triggered the women's rights movement in America.

In “American Ripper,” a new eight-part series premiering on HISTORY on July 11th, the great-great-grandson of H.H. Holmes claims “America’s First Serial Killer” was London’s notorious “Jack the Ripper.”

The historic uprising at the Stonewall Inn in Greenwich Village parked the modern LGBT rights movement in the U.S.

Take a look back at the tragic unsolved murder of the six-year-old beauty queen that still captures America's attention.