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Learn select topics from computer science - algorithms (how we solve common problems in computer science and measure the efficiency of our solutions), cryptography (how we protect secret information), and information theory (how we encode and compress information).
Only have an hour? Learn the basics of programming, making webpages, or creating databases.
Download a real, full-length SAT practice test, watch Sal work through real SAT problems, and get even more practice using our interactive exercises.
Practice all of the skills you'll need for the new SAT. We also have four official practice exams
from the College Board. The October 2015 PSAT is in the style of the new SAT.