Denim is a durable cotton fabric known for its rugged texture and twill weave, traditionally made from 100% cotton. However, modern denim often includes a blend of materials such as polyester or elastane to enhance functionality, comfort, and stretchability. The core structure of denim fabric relies on cotton because of its breathability, strength, and dye-absorption capabilities. Cotton gives denim its classic feel and ability to fade uniquely over time, which is a major part of its aesthetic appeal.