What promotes international trade?

Lets understand trade first.Trade is defined as exchange of goods and services for a price or for another set of goods and services.When such exchange takes place within the boundary of a nation is called domestic trade.When it takes place accross national boundary,it is called intenational trade.International trade is necessitated by inability of a nation to produce certain specified goods and services of its requirement.In such a situation,requirement is fulfilled by importing such goods and services from producing countries.This way, international trade takes place.

International trade is also caused by disparities among nations in technological advancement.Technologically advanced nations keep on helping underadvanced nations by their technology.Sale and purchase of goods, services and technology takes place between nations in international trade.