Thrown over the shoulders of your party dress at a function, paired with your best jeans on the weekend, or styled as part of your smart-casual dress code at the office, leather jackets are the outerwear you're either already obsessed with or are about to be. Likely the first image that comes to mind when you think of a ‘leather jacket’ is the classic biker style motorcycle jacket. Created in the '20s and made popular in the '50s thanks to Hollywood actors like Marlon Brando and James Dean, leather biker jackets are usually shaped to a relaxed or oversized fit for that androgynous effect, but for a more modern style, look for slim silhouettes.