The SAT is an entrance exam used by most colleges and universities to make admissions decisions. The SAT is a multiple-choice, pencil-and-paper test created and administered by the College Board. 

The purpose of the SAT is to measure a high school student's readiness for college, and provide colleges with one common data point that can be used to compare all applicants. College admissions officers will review standardized test scores alongside your high school GPA, the classes you took in high school, letters of recommendation from teachers or mentors, extracurricular activities, admissions interviews, and personal essays. How important SAT scores are in the college application process varies from school to school.

After the reform in 2016, the total score of the new sat was 1600, which was divided into three parts: reading, grammar and mathematics. And the writing part is selective. The result is valid for two years.

SAT Subject Tests are college admission exams on specific subjects. These are the only national admission tests where you choose the tests that best showcase your strengths and interests.

· There are 20 SAT Subject Tests in five general subject areas: English, history, languages, mathematics and science. Each Subject Test is an hour long. They are all multiple-choice and scored on a 200–800 scale.

· Subject Tests test you on your knowledge of subjects on a high school level. The best way to prepare is to take the relevant courses and work hard in them.

· SAT Subject Tests are generally given six times in any given school year, on the same days and in the same test centers as the SAT — but not all 20 tests are offered on every SAT date.

· You can take one, two, or three Subject Tests on any test date.

· You can’t take the SAT and an SAT Subject Test on the same day.

· You choose what tests to take when you register, but on test day, you can add, subtract, or switch tests — with some limitations.  

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