Third-party sellers are individuals or businesses that sell products on platforms like Amazon or eBay without being the original manufacturer. They list their items for sale alongside products from the platform itself, allowing customers to choose from a wider variety of options. These sellers can offer new, used, or refurbished items, often at competitive prices. When shopping from third-party sellers, it's important for customers to check seller ratings and reviews. This helps ensure a positive buying experience, as the quality of service and products can vary. Many platforms provide tools to help buyers assess the reliability of these sellers.