A demi-plié is a fundamental ballet movement where a dancer bends their knees while keeping their heels on the ground. This exercise is essential for developing strength, flexibility, and proper alignment in the legs. It is often performed in various positions, such as first position or second position, and serves as a warm-up for more complex movements. During a demi-plié, the dancer lowers their body by bending the knees outward, ensuring that the knees track over the toes. This movement helps improve balance and prepares the dancer for jumps and turns. Practicing demi-pliés is crucial for building a solid foundation in ballet technique.