Concern the resources businesses use to produce and market the goods and service they require to generate wealth. These include: people with ideas, knowledge, and skills to help produce or provide the goods and services required: land, buildings, vehicles, machinery, equipment; materials such as paper, metal, wood, plastic, food ingredients; and money to purchase these resources. The specific resources, especially raw materials that a business requires, will obviously depend upon the type and quantity of goods and services to be provided. These business resources are usually categorised into four groups: capital, enterprise, land and labour (CELL). Together they are known as the four factors of production.