The Metropolitan Museum of Art embodies large collections of artifacts beginning with Egyptian Art with pieces dating back to the 300.000 B.C, to the 4th century A.D, and ending with modern painting or sculpture. This museum has a variety of collections that come from different geographical regions and periods of time, which makes it a bit hard to follow for a first timer. In order to get a better idea of the Museum and its exhibitions, you can choose to go on a tour of the Highlights.
Should you want to get in deeper in the world of history of art, you can visit the over 2 million pieces which reside in the Museum's permanent collection. You can also check out the site of the Met and its online galleries. The collections of the Met gather about 5 million visitors per year, more than any other landmark in New York.
In order to properly visit the place, you should choose an area of interest and visit it during a day or take the Highlights Tour. One cannot simply see the whole museum or two collections in one day. Check out the suggested itineraries available on the Met website to get an idea of what you might visit later.