One year ago, on January 8, 2011, a young man opened fire on an unsuspecting crowd at a political gathering in a suburban Tucson, Ariz., shopping mall. The gunman used a Glock 19 pistol. Six people died; 13 others were wounded, including U.S. Rep. Gabrielle Giffords. One of the more remarkable facts to emerge from this horrible event was that Giffords also owned a Glock 19.

Invented just 30 years ago by an obscure Austrian curtain-rod manufacturer with little firearm experience, the Glock semiautomatic pistol has become in every sense America's gun. My book, "Glock: The Rise of America's Gun" (Crown, $26.00) outlines the history of the weapon. It is preferred by more U.S. police officers than any other sidearm. It stars in Hollywood movies, television cop shows, true-crime novels, and deadly serious op-ed essays. And it turns up in the hands of mass killers: in Tucson, at Virginia Tech, in Killeen, Texas.

This phenomenal appeal can be traced to the Glock's enormous ammunition capacity, its smooth functioning, its slightly menacing squared-off appearance, and, in the case of some rap songs, its having a name that rhymes with many other words.

Glock swiftly became the Kleenex of firearms, the Google of guns. Everyone knows what a Glock is. Or at least they think they do.

Here are nine things you really need to know about America's gun.

PHOTO GALLERY Glock history

Correction: The original slide image for "Die Hard 2" did not feature a Glock pistol. It has now been replaced with one that, we are pretty sure, does. This was an error committed by The Huffington Post, not by the author of this piece.