What is the difference between CELTA, TEFL, TESOL?

CELTA, TEFL and TESOL are all acronyms used in teaching English as a Foreign Language (TEFL). TEFL refers generally to the industry, but is also widely used to describe a standard course qualification (e.g. a TEFL Certificate). TESOL means Teaching English to Students of Other Languages, and is similarly used. CELTA (Certificate in English Language Teaching to Adults) on the other hand, is a specific, well established, course monitored by the University of Cambridge Local Examinations Syndicate (UCLES).