The concept of the wheelchair has existed for centuries, evolving significantly over time. The earliest known wheelchair, dating back to the 6th century, was a simple chair with wheels. However, it wasn't until the 20th century that wheelchairs began to improve in design and functionality, largely due to advances in materials and technology. The introduction of self-propelled wheelchairs revolutionized mobility for individuals with disabilities. Unlike traditional wheelchairs, which required someone else to push, self-propelled wheelchairs allowed users to maneuver independently, transforming their ability to engage in the world around them.