What is what does fly in fly out mean?

Fly in fly out (FIFO) is a work arrangement in which employees travel to a worksite or project location for a specified period of time and then return home for an equally specified period of time. This is typically used in remote locations or industries such as mining, oil and gas, and construction where the workers live on-site for a few weeks at a time and then return home for a few weeks. The transportation to and from the worksite is usually by plane, hence the name "fly in fly out." This type of work arrangement can come with both benefits and challenges for the workers, as well as the companies that employ them.