The Netherlands is one of the biggest cheese exporters in the world. In every supermarket you can buy many kinds of cheese, of which the Gouda and Edam kind are probably the best-known.
In the centre of Amsterdam you'll find an (increasing) number of cheese shops that cater especially for tourists.
The Dutch use cheese mainly to put on sandwiches. In basically every lunchroom you can get a sandwich with cheese ('broodje kaas').
Cheese is also used in sauces, or just as a snack.
If you want to bring some cheese home as a souvenir, you might want to check with the customs authorities of your country to find out if there are any import restrictions.
Jacobs Hoeve, cheese factory