MILWAUKEE (AP) — The nation's best-selling glass cleaner is turning 75.Windex was introduced during the Great Depression as a simple windshield cleaner. Now there's a family of Windex products specialized for surfaces from mirrors and windows to computer monitors and flat-screen TVs.Windex was developed by The Drackett Company in 1936. The company was bought in 1992 by privately held SC Johnson in Racine.The cleaning solution is easily recognizable by its distinctive blue hue. SC Johnson says the color comes from a dye chosen for consumer appeal.Windex had a cameo role in "My Big Fat Greek Wedding," in which a character's home remedy for any ailment was to "put some Windex on it." SC Johnson says as with any cleaning product, Windex should be used according to the label directions.