You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Imperialism

Context:
Imperialism is defined as "A policy of extending a country’s power and influence through diplomacy or military force." Imperialism is particularly focused on the control that one group, often a state power, has on another group of people. This is often through various forms of "othering" (see other) based on racial, religious, or cultural stereotypes. There are "formal" or "informal" imperialisms. "Formal imperialism" is defined as "physical control or full-fledged colonial rule". "Informal imperialism" is less direct; however, it is still a powerful form of dominance.

Question:
imperialism often divides countries by using which technique?

othering