Final answer:
The year-long discussions for reducing trade barriers under GATT were known as rounds of talks, which evolved over time to include more countries and trade issues, leading to the establishment of the WTO.
Step-by-step explanation:
The year-long discussions for reducing tariffs and non-tariff trade barriers under the General Agreement on Tariffs and Trade (GATT) were called rounds of talks.
These talks initially included a small number of countries and were focused mainly on lowering tariffs. However, since the mid-1960s, the rounds of talks have expanded to include a large number of countries and cover a broader range of trade issues.
The first rounds took place shortly after World War II, where 23 countries came together to form the GATT with the hope of fostering economic recovery through trade liberalization.
The process involved negotiating an agreement to reduce trade barriers, signing the agreement, pausing for a while, and then starting the process over again to negotiate the next agreement. This iterative process eventually evolved into today's World Trade Organization (WTO).