A tag is a keyword or label that categorizes your question with other, similar questions. Using the right tags makes it easier for others to find and answer your question.
Used for challenges where answers make reference to themselves or their characteristics, such as length or character values.
For challenges relating to approximating constants/other numbers.
related to the Brain-flak esoteric language and languages based on Brain-Flak. Note that challenges that require the answers to be in a specific language are generally discouraged.
For challenges that require answers to perform network requests, etc.
related to crossword puzzles.
scored on some metric of their output.
The puzzle or challenge involves repeated application of some transformation to the input. These puzzles often involve mathematical sequences or fractals.
For challenges regarding fitting the most number of a certain shape into another shape, or for packing a number of a certain shape into the most compact form.
Fewest operations measures the number of specified "operations" performed at run time.
combination puzzles that involve moving flat pieces around to achieve a target configuration. Examples are 15-game or 2048.
Used for challenges that require user interaction during their runtime
For challenges involving either three-dimensional graphics, three-dimensional geometry or spatial data structures in three dimensions (e.g. octrees).
Used for challenges that consist of multiple sub-challenges ("holes"), somehow combining the scores into one score. (Note: combining multiple unrelated challenges together is off-topic)
Challenge related to the concept of trees present in graph theory.
related to the Haskell language. Note that challenges that require the answers to be in a specific language are generally discouraged.
exists for historical reasons. New challenges of the type previously posted under this tag are not welcome.
indicates that the challenge involves electrical components such as resistors in some way (e.g. counting the total resistance of a set of resistors).
For challenges asking participants to design a language or parts of a language.
directly related to solving, generating, or otherwise working with the minesweeper game.
For challenges related to topology the mathematical study of open sets.
For challenges that involve error output, such as compiler/interpreter warnings or errors.
Challenges involving behaviour that depends on previous invocations of the solution.
Puzzles involving a word search - a word game that consists of the letters of words placed in a grid, which usually has a rectangular or square shape. Usually, the objective of this puzzle is to find…
Tasks involving writing compilers for various languages or formalisms.
about or related to encoding a plaintext, usually with one or more keys.
For challenges pertaining to a formal grammar often a context free grammar.
is used for challenges specifically related to clocks and the display of absolute time. Usually it should not be used for challenges about relative time.
indicates that the challenge involves creating or decoding error correction - adding bytes to data to ensure that it can be read even if part of it is lost.
For challenges involving doing something at compile-time, rather than run-time. This means that only compiled languages can compete.
related to the Lisp family of languages. Note that challenges that require the answers to be in a specific language are generally discouraged.