TOEFL
The Test of English as a Foreign Language (or TOEFL, pronounced "toe-full") evaluates the ability of an individual to use and understand English in an academic setting. It sometimes is an admission requirement for non-native English speakers at many English-speaking colleges and universities. Additionally, institutions such as government agencies, licensing bodies, businesses, or scholarship programs may require this test. A TOEFL score is valid for two years and then will no longer be officially reported since a candidate's language proficiency could have significantly changed since the date of the test. Colleges and universities usually consider only the most recent TOEFL score.


IELTS
IELTS 'International English Language Testing System', is an international standardised test of English language proficiency. It is jointly managed by University of Cambridge ESOL Examinations, the British Council and IDP Education Pty Ltd, and was established in 1989.


SAT
The SAT Reasoning Test (formerly Scholastic Aptitude Test and Scholastic Assessment Test) is a standardized test for college admissions in the United States. The SAT is owned, published, and developed by the College Board, a non-profit organization in the United States, and was once developed, published, and scored by the Educational Testing Service (ETS). ETS now administers the exam. The College Board claims that the test can determine whether or not a person is ready for college. The current SAT Reasoning Test takes three hours and forty-five minutes and costs $45 ($71 International), excluding late fees. Since the SAT's introduction in 1901, its name and scoring have changed several times. In 2005, the test was renamed to the "SAT Reasoning Test" with possible scores from 600 to 2400 combining test results from three 800-point sections (math, critical reading, and writing), along with other subsections scored separately.