Micellar water is made up of micelles (tiny balls of cleansing oil molecules) suspended in soft water and has completely taken the U.S. by storm.
The little micelles are attracted to dirt and oil, so they are able to draw out impurities without drying out the skin. When you wipe a cotton ball soaked with the cleanser along your face, the micelles adhere to the cotton while pulling makeup, sebum, and any other dirt off the skin.
This cleansing water is so light and gentle that there's no need to rinse it off. This means that the infused moisturizing ingredients will stay behind to be absorbed by your skin.