Getting by with your native language is possible, but if you want to obtain a first-class education, thrive in business, or international relations, or simply expand your horizons, English language is your best bet. English serves the world's need to connect and exchange information in a universal language, which is one of globalisation's and international mobility's most important tools. Thus, EF has measured and created a quality index of the English proficiency of adults from 80 countries where English isn't the native language, and Expat.com looks into the results.