Lemons are citrus fruits known for their bright, tart flavor and high acidity. In the context of alcohol and cocktails, lemons are incredibly versatile, used for their juice, zest, and slices. Lemon juice adds a fresh, tangy flavor that balances the sweetness in drinks, making it a key ingredient in classics like the Whiskey Sour, Tom Collins, and Lemon Drop Martini. Lemon zest can enhance the aroma of cocktails, while lemon slices or twists are often used as garnishes. The vibrant acidity of lemons pairs well with virtually all spirits, adding a refreshing brightness to cocktails.