Byredo Deep Viola (U) Edp 100Ml Top Notes: These are the initial scents that you perceive when you first apply the fragrance.Heart Notes: Also known as middle notes, these scents become noticeable once the top notes fade away. They form the core of the fragrance.Base Notes: These are the final scents that become apparent as the top and middle notes evaporate. They are usually the longest-lasting components of the fragrance.