WTO's trade rules are really pretty simple. The golden rule of trade is that you can't do to others what you don't do to yourself. So a country can't ban the imports of purple foreign cars if that country makes and sells its own purple cars. Another rule is that you must treat all countries the same. Sometimes countries set up tariffs, or taxes on goods from other countries, making the foreign goods more expensive than similar local products.
Tariffs cause big arguments between countries.
Seattle coffee companies export gourmet coffee products all over the world. Wait a minute. They're sure not in our Olympic rain forest or over in the Palouse. When it comes to coffee, we're exporting expertise and experience. Companies such as Tully's Coffee have lots of know-how when it comes to roasting and blending coffee beans.