The headstand (sirshasana in Sanskrit) is also called the king of asanas as the posture has so many benefits for your body and mind. By reversing the normal effects of gravity, it rests the heart, aids circulation and relieves pressure on the lower back. A regular headstand practice helps to prevent back problems and improves memory and concentration. Inverting the body also deepens the breath, bringing a fresh supply of oxygen-rich blood to the brain.
Mastering the headstand requires no great strength. It is largely a matter of conquering fear and believing you can do it. The key to balance is the tripod formed by elbows and hands.