The ACT (American College Testing Assessment) is an examination that is expected to measure a candidate's academic achievement in four basic areas, namely, English, Math, Reading and Sciences. There is also an optional writing test, which includes a short essay. Quite a few universities and colleges require the scores of the ACT examination as a basic requirement for entry.
The ACT exam is for about three hours with a small break between the second and third test. There are usually 215 scored questions that are in the multiple-choice format. The optional writing test is for thirty minutes where an essay test that measures the writing skills is given. More information about ACT can be obtained from www.act.org - the official ACT website.
The question on whether to take up ACT or SAT depends primarily on the strengths and weaknesses of the student taking up the test. But the basic condition on which the test must be chosen is the requirement of the college that the student has applied to. Quite a few colleges accept both ACT and SAT.
Any serious college aspirant will first shortlist the colleges that he or she wants to apply to. Then do a quick check on the websites of the colleges for programs that one is applying to and find out which scores are accepted by that college. Should a need arise, do not hesitate to take both these tests.