Helium is lighter than air, so the balloon will rise due to buoyancy when it is inflated. The advantage of inflating with helium is that balloons can float in the air, giving people a dreamy and romantic effect. Helium is relatively cheap and can be bought at local balloon shops or party shops. It should be noted that when helium is used for inflation, it is necessary to ensure the safety and reliability of the inflation process. It is recommended to follow the instructions provided by the store and follow the relevant safety regulations. Helium will gradually leak out of the balloon, so the inflated balloon may gradually sink. If you want to keep the balloon floating for a longer time, you can use a special helium sealant to extend the storage time of helium.