Many people all over the world dream of going to New York City. When I travel outside the U.S. and tell people where I'm from, they look at me with wide eyes and tell me how much they want to go there.
Start at Grand Central, then walk a few blocks north along Fifth Avenue to window shop and see Rockefeller Center before going to Times Square. If you're interested, St. Patrick's Cathedral is nearby.
The 9/11 Memorial & Museum and looking up at One World Trade Center will be moving things to do, and you should put them on your list.
From the Cronut and Churro Ice Cream Sandwiches to Rainbow Bagels and the Ramen Burger, there is always some crazy new food trend going on in New York City. Google is your best friend when you're in town and want to know what's happening.
People like to see the view from the Empire State Building or Top of the Rock, but I'd suggest going downtown to the One World Trade Center, where the Observatory just opened and gives a view and experience that can't be beat.
NYC is one of the cultural centers of the world, and no trip to the Big Apple would be complete without a visit to at least one museum. It has some of the most famous and varied museums in the world. You could spend a whole week just going to museums.
Walk Around Central Park (you could spend a few days here), The High Line (don't forget to stop for gelato), Fifth Avenue (bring your money! ), and the Brooklyn Bridge (go early to avoid the crowds) are the most popular places in New York City.