Where should I eat in New York City, and which local food or drink is worth trying?

New York's food is a function of who arrived. The Department of City Planning, drawing on the Census Bureau's 2011–2015 American Community Survey, counted 3.21 million foreign-born residents in 2015, up 12 percent from 2.87 million in 2000. That was 38 percent of the city's population and 46 percent of its resident labor force. The three largest countries of birth were the Dominican Republic, China including Taiwan and Hong Kong, and Mexico — the last up 47 percent since 2000 and risen from fifth place to third. Those three facts explain more about where to eat in New York than any list of restaurants: Dominican mangú and pernil in Washington Heights, hand-pulled noodles and Fuzhounese fish balls in Sunset Park and Flushing, Pueblan tlacoyos and barbacoa in Corona and Bushwick.

The deeper layer is older. The Park Service records that the Ellis Island immigration station opened on January 1, 1892 and ran until 1954, processing over 12 million immigrant steamship passengers. The city's signature foods — the bagel, the appetizing counter, pastrami on rye, the coal-oven pizza, the egg cream — were all assembled by people who came through that period, which is why they are specific to New York rather than generic American.

The grading system is a practical tool, not decoration. Scores of 0 to 13 points earn an A, 14 to 27 a B, and 28 or more a C. Grade cards must be posted where people passing by can easily see them, which means you can make a decision from the sidewalk.

The grade card is usually taped at eye height inside the glass, next to the hours, so the ritual of eating out here starts with a half-second glance at a blue-and-white letter before you touch the door.

A B grade is not a warning to walk away — it is a score between 14 and 27 points on a sanitary inspection, and plenty of long-established, much-loved kitchens have carried one. What the system does give you is a consistent, published number across roughly every restaurant in five boroughs, applied by one agency rather than by reviewers. Use it to rule out the bottom, not to pick the top.

• Breakfast — The appetizing counter is a New York institution distinct from a deli: smoked fish and dairy, no meat, a division that dates from kosher practice.
• Midday — Lunch is when the outer-borough kitchens in Flushing, Sunset Park and Jackson Heights run at full strength and shortest notice.
• Late — Pizza by the slice is the city's one genuinely citywide late food, sold from counters rather than tables.

The best eating is a long way from the tourist core: Flushing, Sunset Park, Corona and Washington Heights are all subway rides of 40 minutes or more from Midtown, and dinner there means a late ride back. Cash-only kitchens still exist in all four neighborhoods. Letter grades lapse during the inspection cycle, so a window may show a "Grade Pending" notice rather than a letter, which is a stage in the process and not a verdict.

Pair this with the New York weekend question in this group, which includes the free sites you can reach on the same subway lines, and with the things-to-do answer for museum admissions.