A good riddle can make or break a friendship. If the riddle is good enough, it can draw friends closer together as they try to figure it out. However, a difficult riddle just might make some friends grow frustrated with each other. This is especially true if one friend knows the answer and refuses to give it away when asked.

If you are looking for a riddle to test your friendship, one is storming the Internet right now. The riddle is a simple question. What has a head, a tail, is brown, and has no legs? This is a tough riddle to solve. To help your friends out, you can give them some hints. For example, you can first tell your friends or family the solution to the riddle is not covered in fur. You can also give them a second hint. This hint can let a person know that the answer is a common object you probably see everyday.

This image provided by the US Mint shows the newly redesigned one-cent coin (penny) in 50 years which will be presented Friday Feb. 12, 2009 at the National Park Service’s Abraham Lincoln Birthplace National Historic Site, in Hodgenville, Kentucky. The obverse (heads side) will continue to bear the likeness of President Lincoln currently on the penny. The reverse (tails side) will reflect four different designs, each one representing a different aspect, or theme, of President Lincoln’s life. The themes for the reverse designs represent the four major aspects of Abraham Lincoln’s life include his birth and early childhood in Kentucky; his formative years in Indiana; his professional life in Illinois; and his presidency in Washington, D.C. (AP Photo/US Mint)

If your friend is still struggling, you can give him or her a final hint. Tell them the answer is no longer used in Canada. Have you been able to figure out the solution to the riddle yet? If it still stumps you, don’t forget you can always look to President Abraham Lincoln for guidance! Did you figure it out? It’s a penny! A penny has no fur. It also has a head and a tail. It’s also brown! Let us know how quickly your friends solved the riddle in the comments below!

The earliest known written example of a riddle identifies it as being from ancient Greece, while some Egyptian hieroglyphs show pictures of people asking one another questions that may have been intended as puzzles for children. In medieval times, after Europeans began reading more widely during their Renaissance period, there was renewed interest in all things Greek and Roman. This included not only the work of the ancient philosophers and other knowledge from the classical world, but also riddling. Riddles were popular in medieval times, particularly among royal court members who would take turns coming up with questions for one another. The statements contained in a riddle are usually contrasted by their implied meaning to provide an amusing or witty turn of phrase.

For example, the answer to “What has one horn and a hundred eyes?” is a one-eyed goat.

The terms “riddle” and “enigma” are often used interchangeably in casual usage, but definitionally there is a difference. A riddle requires the use of wordplay or other methods to hide or disguise the solution.

The term “enigma” is sometimes reserved for more complex questions that involve puzzles of logic rather than wordplay, such as an enigmatic puzzle known as Raven paradox or Gödel’s incompleteness theorems.