There are millions of enterprises organized into thousands of industries. When all factors are considered, each enterprise is unique but there is a great deal of overlap (e.g. everyone has a General Ledger and Accounts Payable). The biggest industry in terms of revenue is manufacturing. The second biggest is retail. Although there are thousands of industries, there are only a few dozen intrinsic functions. An ERP system is designed to accommodate many industries using a common base of functions.
Manufacturers create their products from raw materials and parts. This can be as simple as assembling a dozen standard parts to creating products that have thousands of components, hundreds of operations, and require weeks of engineering. Some manufacturers sell their products directly to the end-users; others sell them to distributors or large retailers. Some manufacturers produce millions of identical products; others produce custom, one-off products. The Manufacturing sub-system is key to manufacturers.
Distributors buy products from manufacturers in large quantities (truckloads, railcar loads) and sell them in smaller quantities to retailers. Inventory and Warehousing are important functions for distributors.
Retail stores sell products in small quantities to businesses or consumers. A large retailer might buy directly from the manufacturer; others buy from distributors. Point of Sale (POS) is an important function for retail.
Construction enterprises build things. This can vary from a modest house to a multi-million dollar skyscraper or a six-lane freeway. Job Costing and Project Management are important functions for construction enterprises.
Professional Service enterprises include lawyers, accountants, consultants, architects, and other firms that bill their clients for their services. Since they live or die on billings to clients, timesheets are an important function for professional service enterprises.
For-profit enterprises exist to maximize value for their shareholders. Not-for-profit enterprises exist to maximize services to their clients given the amount of resources they have. Not-for-profits use different accounting practices and produce different financial statements than for-profits