Air plants are from the Tillandsia genus, and there are around 650 different species. They are native to southern United States, Mexico, Central and South America. They are epiphytes, meaning plants that grow without dirt. Air plants grow 'roots' and attach themselves to rocks, trees, or shrubs.
Air plants absorb moisture from rainforest air, and do best with constant humidity. Because of their high humidity needs, they are happiest in a semi enclosed terrarium with a pebble tray. They require good air flow, so be sure to keep them in an open container. Because they grow in trees and shrubs and are often shaded, they cannot tolerate prolonged direct sunlight.
For best success, place in a north, east, or within 5 feet of a south or west facing window, not in direct sunlight. Mist your air plants every day, or give them a 10 minute bath often. Do not let your air plant sit in water between misting or bathing or they will rot. Gently peel off any old or browning leaves from the bottom. They are ready to be misted again when the surface of their leaves are dry.