Poshmark is an online marketplace that allows users to buy and sell new or gently used clothing, shoes, and accessories. Founded in 2011, it operates as a social network where users can create virtual closets, share listings, and follow each other. The platform is accessible via a website and mobile app, making it easy for users to browse and shop. Sellers can list their items by uploading photos and providing descriptions, while buyers can search for specific brands or styles. Poshmark takes a commission on sales, providing a secure payment system and shipping labels to facilitate transactions.