Cartilage at the ends of bones, called articular cartilage, serves several important functions in joints. It provides a smooth, slippery surface that reduces friction, allowing bones to move smoothly against each other. It also acts as a shock absorber, cushioning the joint during impact and distributing forces evenly to prevent damage. Additionally, cartilage helps maintain joint mobility by enabling a full range of motion. However, because it lacks blood supply, cartilage has limited ability to repair itself, and over time it can wear down, leading to conditions like osteoarthritis.