First thing's first, the Digital SAT is NOT the regular SAT on a computer screen. According to the College Board, they have taken, "the opportunity to make the SAT a far better test experience for you."
The test will be taken on a custom-built application called Bluebook that allows for the test to be adaptive. And what does it mean, for a test to be adaptive?
An adaptive test is one that customizes itself to the performance of the student. Meaning, the better a student's performance in section one, the harder their section two questions will be, and the more points each question will be worth. So... ensure to do very well in the first section, so you can score big on the second!
Overall, the test is designed to better ascertain your readiness for college. There is a clear attempt at reducing the stress and anxiety of the test and focusing more on aptly determining your ability to succeed in college.