Mobility is the ability to move freely from place to place. A person with good mobility can walk, run, and get around easily. Someone who breaks their leg loses mobility temporarily and might need crutches. As people age, they sometimes experience reduced mobility and may need a cane or wheelchair to help them move around.

The word also describes how easily people can change their position in society. Social mobility means the ability to improve your circumstances through education, hard work, or opportunity. In a country with high social mobility, a child born into a poor family might become a successful doctor or business owner. In places with low social mobility, people tend to stay in the same economic class they were born into, regardless of their efforts.

Physical mobility transformed human civilization. The invention of the wheel gave people mobility beyond what their own legs could provide. Cars, trains, and airplanes created even greater mobility, letting people travel across continents in hours instead of months. This mobility of people also meant mobility of ideas: when people can move and meet, they can share knowledge, start businesses, and build new communities.

Whether we're talking about a dancer's graceful mobility or a society's economic mobility, the word captures something essential: the freedom and ability to move forward.