This spring version of CS50 is for SEAS concentrators (or secondaries) who were unable to take the course in Fall 2020. All students, including concentrators and non-concentrators, are encouraged to take CS50 in fall term instead. See cs50.harvard.edu/spring for differences between fall term and spring term. Students must register via my.harvard for and attend weekly class meetings via Zoom on Tuesdays, 3pm–5pm ET. Instructor-led tutorials to be arranged. CS50 is ordinarily graded SAT/UNS, though students whose concentration requires letter grades should change their grading status to letter-graded by the term’s fifth Monday. Students may take CS50 SAT/UNS to fulfill the Science and Engineering and Applied Science distribution requirement or the Quantitative Reasoning with Data requirement, but not both. First years may take both CS50 and a freshman seminar SAT/UNS.