ACT and SAT have recently made changes, and these changes have made the tests similar to each other. However, there is still a distinction between the two exams and knowing the difference can help a student choose where to invest their study time.
To find out how a student can best choose which test to take please read the following article. http://college.usatoday.com/2016/02/01/how-to-choose-between-the-act-and-sat/