TESL

Teaching English as a second language (TESL) refers to teaching English to students whose first language is not English, usually offered in a region where English is the dominant language and natural English language immersion situations are apt to be plentiful.

In contrast, teaching English as a foreign language (TEFL) refers to teaching English to students whose first language is not English, usually in a region where English is not the dominant language and natural English language immersion situations are apt to be few. TEFL teaching is considered to be more accessible to teachers with less experience. These teaching jobs are also more prone to exploitation with few companies helping to fight against systemic abuses.

The teaching profession has historically used different names for these two teaching situations; however, the more generic term teaching English to speakers of other languages (TESOL) is increasingly used to describe the profession. Both native speakers and non-native speakers successfully train to be English language teachers. In order to teach English as a Second Language to English Language Learners, or ELL's, one must pass a written and oral test in English to demonstrate proficiency.

The use of these various terms has led to confusion about the training options for both prospective students and for employers. Because there is no global standard for the training of English language teacher, it is important to look beyond the actual acronym/title to the components of the training program. Short term certificate programs that do not have an academic affiliation resulting in credits or degrees (such as CELTA or other non-credit programs) can be a good launching pad for beginning positions internationally, but they will generally not provide sufficient training for a career (unless a person already has substantial experience and a degree in a closely related field). People interested in pursuing a career as an English language teacher should invest in credit-bearing programs that result in a university recognized certificate or degree program (MA/TESOL, MA/Applied Linguistics) particularly if one wants to work in higher education. Because of the confusing certification situation, employers now generally look for a certificate that reflects at least 100 hours of instruction in order to determine if the candidate has sufficient preparation to begin teaching English. Institutions with higher standards will require applicants to possess a master's degree for employment.

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Wikipedia