Teaching English for Speakers of Other Languages, or TESOL, is a discipline in which instructors are educated in methods for teaching non-native English speakers how to read, speak and write the English language. TESOL certificates are administered by a number of bodies in the both the United States and the UK.

Types
There are a number of types of certifications in TESOL. There is no single, authoritative body that accredits TESOL, which means that the value of the certificate generally hinges on the reputation of the institution offering it. Trinity College London and Cambridge University both offer TESOL certificates. Many companies, such as the US-based TEFL International, offer certificates in TESOL, while some U.S. universities offer master's degrees in the subject.

Features
The term "TESOL" is an umbrella term that incorporates many types of courses designed to certify instructors in the teaching of English to non-native speakers, including TEFL and TESL classes. While requirements vary, many intensive courses, if taken full-time, can be completed in four weeks. Classes generally cover both the teaching process, such as skills necessary for effective teaching -- including communication, lesson planning and classroom management -- and language-specific lessons, such as how to instruct students in reading, writing and speaking.

Functions
TESOL certificates are designed to prepare students to take jobs abroad as teachers of foreign languages. The certificates can be considered a type of professional certification, letting employers know that their holder has been schooled in the basic skills necessary to the position. Most certification classes are designed to allow their graduates to attain teaching positions all over the world.

Benefits
Many organizations that hire TESOL instructors demand that their employees hold a teaching certificate from a reputable organization. Among the best known degrees are the Cambridge CELTA and the Trinity CertTESOL. A number of independent organizations, such as the University of Cambridge Local Examinations Syndicate, will also externally validate other organizations. Some companies might value certificates from external validated schools more so than other institutions. Certification courses are also likely to make graduates better teachers than those who undertake only courses of self-study, as TESOL graduates benefit from more experienced instructors.

Misconceptions
There is much confusion regarding the alphabet soup of acronyms that describe the different courses designed to prepare students to teach English as a second language. These include ESL, ESOL, EFL, EAL and TEFL. As stated above, TESOL is an umbrella term describing all of these courses. Organizations hiring TESOL instructors might have specific requirements about what kind of TESOL certificate their employees hold. For instance, some organizations might prefer courses taught in a classroom rather than online, or for instructors to have taken a certain number of hours of classes at a certain school.