Tic-tac-toe, dots and boxes, hangman, and bulls and cows, among others, are all games which can be conducted between two or more players using only a piece of paper and a writing instrument. Unlike board games, paper-and-pen games are particularly well-suited to spontaneous play, regardless of location, because they require no advance preparation beyond obtaining writing materials and conveying the rules to the other player. They can be played while riding in a car, because there are no game pieces which may be knocked over.
Cheating at paper-and-pen games is very difficult, since eraser marks are noticeable, unlike moving somebody's pawn on a chessboard when their attention is diverted. These games also tend to be very simple to teach, accessible to anybody old enough to use a pen dexterously. These games transmit easily between cultures and language environments: if you start a game of tic-tac-toe with a complete stranger, they will almost certainly know how to play along, even if you don't speak the same language.
Paper-and-pen games are usually used to kill time and mitigate boredom, between performing more interesting and demanding activities. It is uncommon for a paper-and-pen game to be the "main attraction" of anybody's day, but it can provide momentary respite between other tasks. Many schoolteachers will hold paper-and-pen games with their students, on a chalkboard or whiteboard instead of on paper, as incentive or a break for entertainment between lessons. In the case of the game of hangman, the word selected as the solution may be relevant to the day's lessons, to encourage the students to retain what they have learned.
Iron Noder 2016, 14/30