A pub-crawl is a night out where you go to several pubs, one after another, and have a drink in each. The point is the moving: you do not settle in one room. Friends do it for a birthday, a last night before a wedding, or just because the evening has no plan. Tourist towns sell it as a packaged walk with a list of doors. It is informal, and it started as British and Irish talk, though other countries now use it too — or they say bar crawl. Though actually, nobody is crawling on the floor. Crawl here is the old joke of going slowly from door to door, a little less steady each time. Some crawls are cheerful and short; some are long drinking sessions, and police reports use the word when the night went badly. You would put it in a message to friends, not on a school form.