See Pharrell Williams's Spectrum of Hats

It's time to celebrate and get 'Happy,' y'all! Pharrell Williams, who turns 41 today, has had quite the year. The Grammy winner, who most recently signed on as judge for season 7 of The Voice, caught our attention in both style and beauty. On top of his already lengthy designer resume (he has his own fashion label Billionaire Boys Club), Williams nabbed a collaboration with Adidas this year, and is teaming up with Comme Des Garcons to create a unisex fragrance, aptly named GIRL, after his hit album.

But if we were to narrow down his most influential plaudits, Williams made an even bigger splash with his handmade Vivienne Westwood felt toppers ($180, viviennewestwood.co.uk)—first making an appearance at the Grammys, and reappearing at four major events, including the Academy Awards. Click through the gallery to see the buzzed-about Mountain hat, in all five different shades.

Grace Gavilanes and Kelsey Glein