Illustration of echo sounding using a multibeam echosounder. The MTVZA sounder received from the Meteor M2-2 satellite by an amateur station Echo sounding or depth sounding is the use of sonar for …

The fifteen puzzle has been computerized (as puzzle video games) and examples are available to play for free online from many Web pages. It is a descendant of the jigsaw puzzle in that its point is to …

A chess puzzle is a puzzle in which knowledge of the pieces and rules of chess is used to logically solve a chess-related problem. The history of chess puzzles reaches back to the Middle Ages and has …

The Echo Wife is a 2021 science fiction thriller novel by Sarah Gailey, published by Tor Books. It follows Doctor Evelyn Caldwell, an accomplished scientist researching cloning, has discovered that her …

An 1850 acrostic by Nathaniel Dearborn, the first letter of each line spelling the name "JENNY LIND" An acrostic is a poem or other word composition in which the first letter (or syllable, or word) of each …

The Zebra Puzzle is a well-known logic puzzle. Many versions of the puzzle exist, including a version published in Life International magazine on December 17, 1962.

The myth is told in Book III of the Metamorphoses and tells the story of Echo, a mountain nymph from Mount Cithaeron, and Narcissus, a hunter from a Thespiae in Boeotia, known for his many admirers …

Example cryptogram. When decoded it reads: "Style and structure are the essence of a book; great ideas are hogwash." -Vladimir Nabokov A cryptogram is a type of puzzle that consists of a short …