TOEFL
The TOEFL test consists of 4 sections. Reading Comprehension - you are required to understand a written text and to answer questions about the content and structure.
Listening- you are required to understand and remember an audio segment. You may take notes during the listening.
Speaking - A short 20-minute segment where you are tested on your speaking abilities via the internet.
Writting - there are two different essay assignments, both of which are done on the computer. The test takes approximately 4 hours to complete.
GMAT
The Graduate Management Admission Test (GMAT) is a standardized test that B-school aspirants need to take if they are looking to join an accredited MBA program.
GMAT scores are valid for a period of five years, and the test has the stamp of approval of leading B-schools across the world.
While admissions committees do consider many other factors, including grades, transcripts, skills, work experience, essays, resume, and interview, the GMAT score is a critical criterion to get into a competitive B-school.
GRE
GRE is a standardized test for admissions into graduate school in the US. It is mandatory for most students aspiring for Masters or PhD (other than in Law or Medicine) in several universities in the US. The GRE revised General Test is accepted at thousands of graduate and business schools as well as departments and divisions within these schools.
The General Test measures verbal reasoning, quantitative reasoning, and critical thinking and analytical writing skills that are not related to any specific field of study.