Sparkling water is made by adding carbon dioxide under pressure. After carbonation, it foams and has a refreshing taste like soda. As sparkling water contains no sugar or calorie, it reduces sugar intake and causes obese individuals who favour soft drinks to increase their chances of drinking water. 

The presence of carbonation has little effect on the body's response to ingested water, so sparkling water is just as hydrating as non-carbonated water. But everyone has a different preference for carbonated drinks, some more or some less. And carbonation may cause bloating during physical activity and can prevent an athlete from drinking enough, so stilled water is recommended during exercise. 

Additional reading materials:

Is sparkling water good for you? 

Hydration of sparkling water