Trade barriers come in many forms. Quota is one. This is when a country sets a limit to the imported products. This is done for a number of reasons. One is because the government of the importing country wants to protect the local manufacturers.

In this way, trade barriers can affect the international trade because it does not promote free trade. When countries trade with each other they do not want to have trade barriers because it can result in an unfair trade where country A may export goods to country B but country B cannot do vice versa because country A sets up trade barriers such that it makes it very difficult for country B to export. One example is a trade barrier concerning with health and safety.