"The TOEFL test measures your ability to use and understand the English language as it’s read, written, heard and spoken in the university classroom. As the most accepted English-language test in the world, more than 8,000 universities, agencies, and other institutions in more than 130 countries accept the TOEFL test as part of their admissions criteria." 

--from "All about the TOEFL Test: What You Need to Know", on the TOEFL official website.