Twenty Four Seven

In commerce and industry, 24/7 or 24-7 service (usually spoken "twenty-four seven") is service that is available any time and, usually, every day. Alternate orthography for the numerical part includes 24x7 (usually spoken "twenty-four by seven"). The numerals stand for "24 hours a day, 7 days a week". Less commonly used, 24/7/52 (adding "52 weeks") and 24/7/365 service (adding "365 days") make clear that service is available every day of the year.

Synonyms include round-the-clock service (with or without hyphens), especially in British English, and nonstop service.

The Oxford English Dictionary (OED) defines the term as "twenty-four hours a day, seven days a week; constantly". It lists its first reference to 24/7 as from US magazine Sports Illustrated in 1983. In that story, LSU player Jerry Reynolds described his jump shot in just such a way - plus 365.

24/7 service might be offered by a supermarket, convenience store, ATM, automated online assistant, filling station, restaurant, concierge services or a staffed datacenter, or a staffing company that specializes in providing nurses since often nurses cover shifts 24/7 at hospital which are open 24/7. 24/7 services may also include taxicabs, security services, and in densely populated urban areas, construction crews.

Public 24/7 services often include those provided by, emergency medical providers, police, fire and emergency telephone numbers, such as 9-1-1 in North America. Transport services like Airports, Airlines, and Ferry services and in some cases Train and Bus may provide 24 hour service.

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Wikipedia