Blue-collar work may involve skilled or unskilled labor. The type of work may involve manufacturing, warehousing, mining, excavation, electricity generation and power plant operations, custodial work, farming, commercial fishing, logging, landscaping, pest control, food processing, oil field work, waste collection and disposal, recycling, construction, maintenance, shipping, driving, trucking and many other types of physical work. Blue-collar work often involves something being physically built or maintained.