Despite numerous changes in the US university application process, some truths remain the same -- namely, you need to ace your SATs if you plan to attend a top-notch university.

The SAT, or Scholastic Aptitude Test, is designed to gauge aspiring US undergraduates. It measures the ability of candidates to solve problems and use reasoning skills at the level necessary for US universities.

Most colleges and universities use the SAT as one indicator of a student's readiness to do university-level work. Other criteria include class rank, marks (Grade Point Average), extracurricular activities, personal essays and recommendations.

Starting in 1993, the SAT split into the SAT I: Reasoning Test and the SAT II: Subject Tests. In general, universities only require SAT I, but the most exclusive schools often require two or more SAT II Subject Tests.

SAT is held seven times in a year in the USA, Puerto Rico, and US Territories, and six times a year at over 650 other overseas locations.

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SAT I

SAT I is a three-hour test that measures verbal and mathematical reasoning skills students have developed over time, and skills they need to be successful at university.
 
Good SAT scores can help you gain admission to selective schools and earn merit-based financial assistance.

The SAT I contains Verbal, Math and Writing components, each worth one-third of the final score. There are three Verbal sections, three Math sections and two Writing sections.

In addition, there is a 20 minute 'dummy' section, formally called the Variable or Equation Section. This section does not count towards your individual score; it is used to try out new questions for the future editions of SAT. You won't know which section is the 'dummy', so try your hardest throughout.

The first and last sections are always Writing, the first being a 25-minute Writing Essay and the last a 10-minute Multiple Choice writing section. Out of the remaining seven sections, four are 25 minutes long each, and the other three (including the dummy) are 20 minutes long each.

A systematic chart of the question types and and number in each section are listed below:

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SAT II

SAT II: Subject Tests are an hour long, and comprise mostly multiple-choice questions. They measure how much students know about a particular academic subject and how well they can apply that knowledge.

Subject Tests fall into five general subject areas: English, History and Social Studies, Mathematics, Science and Foreign Languages.

The following chart demonstrates the available options:

In Part II of this feature, we'll look at testing dates, test fees and how to apply.

Part II -- SAT: Registration details

Atul Prashar is an educational consultant with Top Careers and You, an organisation which prepares candidates for leading competitive examinations like CAT, GRE, and GMAT.