Holy water is used in different religions whether it is Hindu or Christian. Every religion has its own meaning and its use for the purpose of water purification. Whenever you go into a temple you are required to use the water so that you become pure and then you can perform all the rituals.
Christians also use this water to make them pure and divine. It is like a gift offered by the temple priest or bishop of the church. You can buy holy water which is blessed by Pope Francis from various web sources.
Regardless of the Holy Water, you also have the Holy Oil or better known as the Anointing oils are added to give a nice smell to the water. You'll find these oils in the four corners of the church.
When you are going into the church then you can take it as a blessing and do your prayers. This oil is made from plants that have medicinal value and so they smell wonderful. They are used to provide various types of essence to the water.
When the bishop or priest praying they sprinkled holy water on the people who gathered there. It is considered that the water droplets are blessings from God showers on people. Water is stored in a special container called "aspersory" and the stick is dipped in it.
Through sticks sprinkled with water droplets on everyone after they have completed their prayers. Therefore, it is the best way to make people come closer to God and feel the divine presence.
Water is not only used in temples and churches, but people also use it for personal reasons. Because they do not have a special container so that most of them use a flask to keep the water together with the Anointing oil.