Curious Cheetah

Puzzle Encyclopedia


This section of my webpage is dedicated to information about grid-based logic puzzles. To qualify, these puzzles should be self-contained and language-independent. The primary thing needed to solve these is logic.
The most famous of these is certainly Sudoku. The precursor to Sudoku was a puzzle called Number Place, apparently developed by Howard Garns and first appearing in Dell's puzzle magazines in 1979. While most of Dell's puzzles require information provided outside the grid, and many rely on cultural knowledge or specific languages, Number Place required only the grid itself.
The Japanese puzzle company Nikoli imported the puzzle into Japan in 1984 and went on to make some key changes. First, the number of givens was set at a maximum of 32; second, the puzzle clues were required to be symmetrical. These changes allowed Sudoku creators to explore more creative avenues.
Once Sudoku exploded in popularity, the variations began to pile up. Now there are a dizzying number of variants, some of which are given as examples in the museum. In addition to Sudoku, there are a wide variety of other grid-based puzzles, many of which pre-date Sudoku.

Puzzle Characteristics

In order to qualify for this site, a puzzle has to be almost entirely self-contained. In a few cases, such as Battleships and Star Battle, there are a few clues that sit outside the grid itself; however, puzzles like number crosswords, which are language-independent but rely on a long list of clues outside the grid, are not included.
Puzzles also have to be language-independent. Many do have a mathematical component, and some (such as Tents and Horror Mirror Maze) have a cultural component. However, those components take only a few minutes at most to learn, and thus do not present a significant obstacle for solvers who haven't been exposed to them before.
Finally, puzzles have be solvable using paper and pencil. There are some self-contained puzzles that require moving tiles about or other controls that are well-suited to being done on a computer but don't work well on paper.
The puzzles on this site are not meant to be a comprehensive list. There are dozens of prolific puzzle creators currently active, and even a full compilation of every puzzle created by just those people would be unmanageably long; many of their puzzles are variants of variants, or created for a single publication. I've tried to include the major puzzle types, as well as the qualifying puzzles from janko.at's major listing, BrainBashers.com's Japanese puzzle set, and Nikoli. However, even those lists continue to grow.
The categories are meant to group similar puzzles, but many of the puzzles strattle different categories. The Basic Index lists the most common name for each puzzle (to the best of my knowledge), while the Full Index lists variant names as well; for instance, only Slitherlink appears on the Basic Index, while Fences, Loopy, and many others appear on the Full Index.
In some cases, I've provided a sample puzzle. The sample puzzles are of my own creation, based on the rules provided.

I hope you enjoy your visit!

I also encourage you to visit the various sites on the Links page. My favorites are R├Ątsel, Puzzles und anderer Denksport (janko.at) and BrainBashers.