In gridiron football, a sack occurs when the quarterback is tackled behind the line of scrimmage before he can throw a forward pass, when the quarterback is tackled behind the line of scrimmage in the "pocket" and his intent is unclear, or when a passer runs out of bounds behind the line of scrimmage due to defensive pressure. This occurs if the opposing team's defensive line, linebackers or defensive backs are able to apply pass pressure to get past blocking players of the offensive team, or if the quarterback is unable to find a back to hand the ball off to or an available eligible receiver to catch the ball, allowing the defense a longer opportunity to tackle the quarterback. Performing a sack is advantageous for the defending team as the offense loses a down, the line of scrimmage retreats several yards. Better for the defense is a sack causing the quarterback to fumble the ball at or behind the line of scrimmage. A quarterback, pressured but avoids a sack can still be adversely affected by being forced to hurry.

In the National Football League, it is possible to record a sack for zero yards. The QB must pass the statistical line of scrimmage to avoid the sack. If a passer is sacked in his own end zone, the result is a safety and the defending team is awarded two points, unless the football is fumbled and recovered either in the end zone by the defense, or outside the end zone. To be considered a sack the quarterback must intend to throw a forward pass. If the play is designed for the quarterback to rush the ball, any loss is subtracted from the quarterback's rushing total. If the quarterback's intent is not obvious, statisticians use certain criteria, such as the offensive line blocking scheme, to decide. Unique situations where a loss reduces a quarterback's rushing total are "kneel downs". A player will receive credit for half of a sack when multiple players contribute to the sacking of a quarterback if more than two players contributed. In the NFL yards lost on the play are added as negative yardage to the team's passing totals.

The NCAA subtracts sack yardage from individual rushing totals. The term "sack" was first popularized by Hall of Fame defensive end Deacon Jones in the 1960s, who felt that a sack devastated the offense in the same way that a city was devastated when it was sacked. According to former NFL coach Marv Levy, it was Washington Redskins coach George Allen who coined the term when referring to Dallas Cowboys quarterback Craig Morton. Allen purportedly stated before a game, "Before we play those Dallas Cowboys, we’re going to take that Morton salt and pour him into a sack." Prior to "sack", the term "dump" was used, the NFL's statistical office recorded all sacks under "dumping the passer". The NFL only began to keep track of times passers lost yardage in 1961 and no credit was given to the defensive player responsible until 1982. Researcher John Turney of the Pro Football Researchers Association estimated that Jones recorded 173½ sacks in his career. Controversial NFL rule changes made for the 2018 season prohibit tacklers landing on the quarterback after making a sack, with the punishment being a roughing the passer penalty.

Of all forms of defensive pressure against the opposition's passer, sacks provide the most immediate impact by ending the offensive play. However, quarterbacks sometimes avoid a sack by throwing an incomplete pass or risking an interception. According to Football Outsiders, a quarterback hurry is the most common form of pass pressure. In the 2009 NFL season, there were 1,106 sacks and 3,268 hurries, a hurried quarterback averaged fewer yards per pass play compared to the average pass play; these records are from 1982 onwards, the year the NFL started recording sacks. NFL single-season sacks: 22.5, Michael Strahan, 2001 NFL career sacks: 200, Bruce Smith, 1985–2003 NFL single-game sacks: 7, Derrick Thomas, November 11, 1990 vs. Seattle Seahawks NFL sacks, rookie season: 14.5, Jevon Kearse, 1999 NFL seasons with 20 or more sacks: 2, J. J. Watt, 2012 & 2014 NFL most consecutive games recording a sack: 69, Tampa Bay, 1999–2003 NFL career sacks taken: 525, Brett Favre, 1991–2010 NFL single-season sacks taken: 76, David Carr, 2002 NFL game sacks taken: 12, Warren Moon, September 29, 1985 and Donovan McNabb, September 30, 2007 NFL Super Bowl most sacks in a single game, 12 Carolina vs. Denver, 50 NFL Super Bowl most sacks by a player in a single game, 3Reggie White – Green Bay vs.

New England, XXXI Darnell Dockett – Arizona vs. Pittsburgh, XLIII Kony Ealy – Carolina vs. Denver, 50 Grady Jarrett – Atlanta vs. New England, LINFL Super Bowl most sacks, career 4.5, Charles Haley – 5 games San Francisco XXIII, XXIV, Dallas XXVII, XXVIII, XXX List of National Football League annual sacks leaders List of National Football League career sacks leaders The Blind Side: Evolution of a Game – non-fiction book by Michael Lewis Sack Story, an article describing the controversy over the sack record Pro-football-reference.com enumeration of career sack leaders

Konevitsan kirkonkellot is a Karelian folk melody, best known as the 1975 recording of Finnish music group Piirpauke. It repeats the chime of the church bells of the Konevsky Monastery in Lake Ladoga; the melody was first recorded by kantele player Ulla Katajavuori in 1952. Other recorded versions include the 1978 version by Matti Kontio, Martti Pokela and Eeva-Leena Sariola, the 2002 version by heavy metal band Sentenced, used as an intro in their album The Cold White Light. Piirpauke's Konevitsan kirkonkellot was released in their 1975 debut album Piirpauke; the song is composed of two parts of the original theme with an improvised part in the middle. The improvised part is known of the classic guitar solo by Hasse Walli. French horn was played by 17-year-old music student Esa-Pekka Salonen, who became a famous conductor. Live versions are included in Piirpauke's albums Historia of Piirpauke Vol. 1 and Metamorphosis – Live 1977–1995

Antonius Jacobus Leonardus van Hooff is a Dutch historian of antiquity, author and a former docent. From 2009 until 2015, he chaired the freethinkers association De Vrije Gedachte. In 1971, Van Hooff graduated with the dissertation Pax romana: een studie van het Romeinse imperialisme; until 2008, Van Hooff was docent in ancient history at the Radboud University Nijmegen. He specialises in classical antiquity, publishes in various newspapers and magazines, he wrote several books, including Nero & Seneca and Marcus Aurelius. Van Hooff is a republican and a member of the Republican Society. On 3 December 2014, Van Hooff held the first Hans van den Bergh Lecture of the New Republican Society in De Balie. Zelfdoding in de antieke wereld /From Autothanasia to Suicide. Self-killing in Classical Antiquity De vonk van Spartacus: het voortleven van een antieke rebel Nero & Seneca. De despoot en de denker Athene. Het leven van de eerste democratie Marcus Aurelius. De keizer-filosoof Klassiek. Geschiedenis van de Grieks-Romeinse wereld Keizers van het Colosseum.

Vespasianus, Titus en Domitianus Sterven in stijl. Leven met de dood in de klassieke oudheid Columns in De Gelderlander