Capture the flag

Capture the Flag (CTF) is a traditional competitive sport played by two or more teams.

The primary objective is to seize an opponent's flag and return it safely to one's own base. This flag is often a piece of fabric, but it can be any small, portable object. For nighttime matches, players may use lanterns, glowsticks, or flashlights as markers. The game relies on strategic movement, teamwork, and territorial control. It can be played in various environments, from open fields to enclosed urban spaces.

To begin, a playing field is divided into two distinct halves called territories. Each team is assigned to one territory and protects their own flag, which is usually placed at the rear of their side. While inside their own territory, players are considered "safe" and cannot be tagged. However, once a player crosses the boundary into enemy territory, they become vulnerable. If an opponent tags them, the player must follow specific rules. They might be sent to a "jail" area, frozen in place, or even forced to join the opposing team.

Rules regarding the flag and jail vary significantly between different versions of the game. In some games, a tagged player must go to a designated jail until a teammate rescues them. This rescue might happen after a set time, such as three minutes, or through a teammate's intervention. When a player is tagged while actually carrying the flag, the flag's fate depends on the local rules. In one variant, the flag returns to its original starting position. In another, the flag remains exactly where the player was tagged. This second method can make offensive play easier because the flag moves closer to the center line over time.

There are many diverse ways to play this game, ranging from physical variations to tactical shifts. One version uses bandannas tucked into pockets; instead of tagging, players must pull the opponent's bandanna to capture them. Another version is called "Stealing Sticks," popular in the British Isles, the United States, and Australia. In this version, players attempt to take sticks, hats, or coats from a goal rather than a flag. Some modern players use airsoft, paintball, or Nerf equipment to play. In these versions, players who are hit must "respawn" by sitting out for a predetermined amount of time.

Capture the Flag has a documented history stretching back to the 19th century. In 1860, Wilhelm Lübeck described a game called Fahnenbarlauf in a German gymnastic manual. During that century, it was often viewed as a variation of the European game Barlaufen. English-language descriptions emerged in the early 1900s. For example, Robert Baden-Powell included "Flag Raiding" in his 1908 book, "Scouting for Boys." By 1920, the Boy Scouts of America had included the game in their official handbook.

Technology has also adopted the mechanics of Capture the Flag. In 1984, the game Bannercatch was released for the Apple II and Commodore 64. This educational game used quadrants like "home," "enemy," and "no-mans land" to simulate the sport. In 1992, Richard Carr released a turn-based strategy game for MS-DOS. More recently, the concept has moved into the digital realm of computer security. In these professional competitions, "flags" are actually secrets hidden within vulnerable programs or websites.

Competitors must find these secrets to succeed.

Today, the game remains a popular way for people to connect through physical and digital play. Urban gaming trends have brought the game back to city streets, where players use cellphones to communicate. One long-running example takes place at the University of Minnesota on the Northrop Mall. On Fridays, this event can attract anywhere from 50 to several hundred participants. Whether it is played on a grassy field, in a city, or through a computer screen, the core challenge of the game remains the same.