The main differences between EFL and ESL are the students and the location where English is being taught to speakers of other languages.
Starting with the basics, EFL stands for English as a Foreign Language and ESL stands for English as a Second Language. More inclusive ESL acronyms are ESOL and TESOL. ESOL stands for English for Speakers of Other Languages. TESOL stands for Teaching English to Speakers of Other Languages.
TEFL stands for Teaching English as a Foreign Language. TESL stands for Teaching English as a Second Language. An English teacher who teaches English to speakers of other languages in a non-English speaking country is teaching EFL. For example, an American living and teaching English in France is a TEFL teacher. His or her students are mostly likely French and their first language (L1) is French. The students are studying EFL.
A teacher living and teaching English in an English speaking country, such as the U.S. or Canada, is teaching ESL. The teacher’s (or tutor's) students are mostly likely students who are from non-English speaking countries, but are now living and studying English in an English-speaking country. The English language learner (ELL) may be living permanently in the country or may just be visiting the country.
Thus, bilingualism is a feature not just of individuals, but also of societies.
Societies in which two languages are used regularly, or in which more than one language has official status or a recurrent function, can be called bilingual. For example, Canada is a bilingual country because French and English are both official languages, even though many citizens of Canada are monolingual English speakers. Saudi Arabia is also a bilingual society, as most Saudis speak both Arabic and English, though English has no official status. The nature of individual bilingualism is quite different in different communities. For example, there are those where bilingualism is the norm for all educated citizens as it is, in relatively small language communities like Scandinavia and The Netherlands. In other countries where bilingualism is the norm for the minority language speakers but not those with the greatest political or economic power in the society (e.g., for Quechua speakers in Peru, for Turkish speakers in the Netherlands, for Spanish speakers in the United States); and those where bilingualism is the norm for the upper classes and better educated but not the relatively powerless (e.g., Colombia). It must be noted that the United States and other traditionally English-speaking countries observe a norm of monolingualism (low expectations for second/foreign language proficiency, low value placed on immigrant languages, universal emphasis on the need to speak English) that is possible only for speakers of a 'language of wider communication' living in an economy that is globally highly influential. In Chile, English is spoken as a foreign language and as Spanish-speaking country is observed a norm of monolingualism with a high expectation for a foreign language proficiency on the need to communicate in English .
