The Heckscher-Ohlin theory is an economic model that explains how countries trade based on their resources. It suggests that a country will export goods that use its abundant resources and import goods that require resources that are scarce. For example, a country rich in labor will export labor-intensive products, while a country rich in capital will export capital-intensive goods. This theory emphasizes the importance of factor endowments, which are the resources available to a country, such as land, labor, and capital. By focusing on these factors, the Heckscher-Ohlin theory helps to explain patterns of international trade and how countries can benefit from specializing in what they produce best.