Wholesaling involves selling products or services to businesses for resale or operational use, differing from retailing by focusing on efficiency in larger transactions and a narrower diversity of offerings. Wholesalers provide essential functions such as risk bearing, financing, and market information, and can be categorized into merchant wholesalers, agent wholesalers, and manufacturers' sales facilities. Merchant wholesalers offer a full suite of services, while agents negotiate sales without taking title to goods, enhancing the distribution process.