Fragrance notes are the different layers of scent that make up a perfume. They are typically categorized into three groups: top notes, middle notes, and base notes. Top notes are the initial scents you smell when you first apply a fragrance; they are usually light and evaporate quickly. Middle notes, or heart notes, emerge after the top notes fade and form the core of the fragrance, while base notes provide depth and longevity, lingering on the skin for hours. Each note plays a crucial role in the overall experience of a fragrance. For example, citrus and herb scents often serve as top notes, while floral and spice notes are common in the middle. Base notes can include rich elements like vanilla or amber, which help to anchor the fragrance. Understanding these notes can enhance your appreciation of perfumes and help you choose scents that suit your preferences.