If you had to choose one thing that separates whiskey from other spirits, most likely the first thing that comes to mind is the importance of barrel aging. While time in wooden barrels before bottling is part of the production of some wine, rum, and tequila, it is nearly ubiquitous today in all whiskey styles.
Historically, whiskey was consumed unaged, and was perfectly clear. Think of what we today call New Make, White Dog, Poitin, or Moonshine. What started as an accidental change in flavor (for the better!) that resulted from transporting whiskey from small family stills to urban city bars has turned into a proud tradition and a fundamental component of the drink.
Read more about finishing whiskey here.
As you will see in the following infographic, there is a lot that goes into barrels (aside from the whiskey). There are different sizes, different materials, and different terms to know. This is all about whiskey barrels!