Being flexible has several benefits. It allows joints to move through their full range of motion, enhances sports performance, improves posture, and reduces injury risk. There are different types of stretching, including static, PNF, and ballistic stretching. Static stretching is safest and involves holding a stretch for 15-30 seconds without pain. Flexibility can be improved over time by following the principles of overload, progression, and specificity in stretching exercises.