For a general treatment of theories, see theory. A scientific theory is a well-substantiated explanation of some aspect of the natural world that is acquired through the scientific method and repeatedly tested and confirmed through observation and experimentation.
A vendor, or a supplier, is a supply chain management term that means anyone who provides goods or services to a company or individuals. A vendor often manufactures inventoriable items, and sells those items to a customer.Typically vendors are tracked in either a finance system or a warehouse management system.Vendor' generally applies only to the immediate vendor, or the organization that is paid for the goods, rather than to the original manufacturer or the organization performing the service if it is different from the immediate supplier.
Retailers are vendors of products to consumers. In information technology as well as in other industries, the term is commonly applied to suppliers of goods and services to other companies. A tier 1 vendor is a large and well-known vendor, often enjoying national or international recognition and acceptance.Tier 1 vendors may be both manufacturers and value-added resellers (VAR s). A tier 2 vendor is a smaller and less well-known provider that is often also limited in its geographic coverage as well.n information technology as well as in other industries, the term is commonly applied to suppliers of goods and services to other companies. A tier 1 vendor is a large and well-known vendor, often enjoying national or international recognition and acceptance.