Poshmark is an online marketplace that allows users to buy and sell new and used clothing, shoes, and accessories. The company was founded in 2011 and is headquartered in Redwood City, California. Poshmark's platform is designed to make it easy for users to buy and sell items, with features like in-app payments, shipping labels, and seller ratings. Poshmark has raised over $150 million in funding and has been recognized as one of the fastest-growing companies in the United States.