A Cafeteria (American English, later on AE) is also referred to as a dining hall or canteen (British English, later on BE) is a type of food service location in which there is little or no waiting staff table service, whether a restaurant or within an institution such as a large office building or school; a school dining location. Canteens (BE) or Cafeterias (AE) are different from coffeehouses, despite being the Spanish translation of the English term.

Instead of table service, there are food-serving counters/stalls, either in a line or allowing arbitrary walking paths. Customers take the food they require as they walk along, placing it on a tray.

In some dictionaries or cultures the context might be different. So what is the difference between “canteen (BE)” and “cafeteria (AE)” a question with too many answers on the English Language & Usage Stack Exchange's website :

1- "Canteen" tends to mean commissary associated with an office/factory. You CAN also use "Cafeteria" in the same way, but "Canteen" is more specific, more normal.

2- "Cafeteria" can mean the cafe/restaurant, for customers, YOU FIND IN A LARGE DEPARTMENT STORE. (Typically either in the basement or on the top floor.)**

3- "Canteen" - generally - tends to be a bit derogatory and/or old-fashioned.

4- Note that a "Cafeteria" is specifically more down-market (cheaper, worse) than a "restaurant." Specifically note that "Cafeteria" always implies you get the food from a long service area - with trays, you know? And carry the food yourself, on trays, to an unserved table. In contrast at a "restaurant" or "cafe" you sit down and are served.

5- Generally this is all more UK than USA, as others have pointed out.

6- In my opinion -- both words would be easily understood, by every English speaker, in every country. If you said "the factory canteen" (or cafeteria) every English-speaker everywhere would understand you - but to repeat point (5), it is odder and perhaps "British-sounding" in the USA. There are some claims by commenters from the USA that some people in the USA would not know what the word means.

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Note added at 1 day17 hrs (2015-11-07 21:45:06 GMT)
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Definition The definition of a canteen is a place where food is provided in a military camp, college or other organization, or a small container for holding drinking liquids.