Riddles have a distinguished literary ancestry, although the contemporary sort of conundrum that passes under the name of "riddle" may not make this obvious. Riddles occur extensively in Old English poetry, and also in the Old Norse literature of the Elder Edda and the skalds. The Exeter Book, a manuscript in Old English, preserves almost sixty versified riddles from the Old English literature. An example:
In Greek mythology, riddles were the province of the Sphinx, a female monster who challenged passersby with riddles; those who failed to guess them were devoured. She famously asked Oedipus, "What is the animal that goes about on four legs in the morning, on two legs at noon, and on three in the evening?" The correct answer given by Oedipus was "Man," who crawls as a baby, walks upright as an adult, and goes with the help of a walking stick when elderly.
In J.R.R. Tolkien's The Hobbit, Gollum challenges Bilbo Baggins to a riddle competition; Bilbo wins the competition by asking Gollum, "What have I got in my pocket?", which Gollum could not answer. The answer, of course, was the One Ring, which Gollum had lost and Bilbo had since found.
In the Batman comic books, one of the hero's best known enemies is The Riddler who is personally compelled to supply clues about his upcoming crimes to his enemies in the form of riddles and puzzles. Stereotypically, they are the kind of simple riddles as described below, but modern treatments generally prefer to have the character use more sophisticated puzzles.
Contemporary riddles typically use puns and double meanings for humorous effect, rather than to puzzle the butt of the joke, as in:
A close relation the riddle is the trick question, which can be used to humiliate the answerer. They generally either have no good answer at all, or have a number of natural answers of which one or more can under closer scrutiny be ridiculed.
Some examples: