A "fixie," short for fixed-gear bicycle, is a type of bike that has a single gear and no freewheel mechanism. This means that the pedals are always in motion when the bike is moving, allowing the rider to control speed and braking by pedaling backward. Fixies are popular among urban cyclists for their simplicity, lightweight design, and minimal maintenance requirements. Riders of fixies often appreciate the direct connection between the bike and the rider, as it provides a unique riding experience. Many fixie enthusiasts customize their bikes with colorful frames and accessories, making them a popular choice in the cycling community.