From the Overview: "The World Trade Organization (WTO) was established on January 1, 1995, following the ratification of the Uruguay Round Agreements and today includes 164 members. [...] The WTO has three basic functions: (1) administers existing agreements; (2) serves as a negotiating forum for new trade liberalization; and (3) provides a mechanism to settle trade disputes among the parties. The multiple WTO Agreements cover trade in goods, services, and agriculture; remove tariff and nontariff barriers; and establish rules on government practices that directly relate to trade--for example, trade remedies, technical barriers to trade, customs valuation, intellectual property rights, and government procurement. The Agreements are based on the principles of nondiscrimination among countries, national treatment, and transparency of trade rules and regulations. Some exceptions, however, such as preferential treatment for developing countries and regional and bilateral free trade agreements, are allowed."
CRS In Focus, IF10002
Congressional Research Service: https://crsreports.congress.gov/