In Britain it is popular , in America it is vey rare.

Here is the page on "the gap year" on the British Council site for English learners. http://learnenglishteens.britishcouncil.org/uk-now/read-uk/gap-year It is informative and it helps English learners master the topical vocabulary and the main ideas. Click on the language exercises below the article to get the maximum benefit.

There are different goals and motivation: 1. Exotic adventure - Africa, Nepal, Tibet, the Caribbean, Indochina, India 2. Politics - Washington D.C. as congressman's aide 3. Humanitarian and wildlife projects - Africa 4. Linguistic immersion - whichever country is right for the language of choice 5. To stay with some rich friends and play - wherever the friends may be: Dubai, Rio, Beijing, Monte Carlo, Florence, Paris, New York …

It's very popular in Australia. Travelling through Europe is almost a rite of passage here.