This is CS50x 2021, an older version of the course. See cs50.harvard.edu/x for the latest!

This is CS50x

OpenCourseWare

David J. Malan
malan@harvard.edu
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🍿 CS50x Movie Night 2022
CS50x Puzzle Day 2022
How to Prepare for Technical Interviews
Zoom Meetings

CS50 Educator Workshop 2021
CS50’s New Year’s Seminars
Gallery of Final Projects
What’s new for 2021?

Week 0 Scratch
Week 1 C
Week 2 Arrays
Week 3 Algorithms
Week 4 Memory
Week 5 Data Structures
Week 6 Python
Week 7 SQL
Week 8 HTML, CSS, JavaScript
Week 9 Flask
Week 10 Ethics

Security
Artificial Intelligence

Final Project

Academic Honesty
CS50 Certificate
FAQs
Gradebook
Staff
Syllabus

Ed Discussion for Q&A
Quick Start Guide

edX
YouTube

CS50 IDE
CSS Tutorial
Flask Quickstart
HTML Tutorial
Jinja Template Designer Documentation
Manual Pages
Python Documentation
Scratch
SQL Tutorial
Style Guide

Changelog
Status Page

Communities
Clubhouse
Discord Q&A
Ed Q&A
Facebook Group Q&A
Facebook Page
GitHub
Gitter Q&A
Instagram
LinkedIn Group
LinkedIn Page
Medium
Quora
Reddit Q&A
Slack Q&A
Snapchat
SoundCloud
Stack Exchange Q&A
TikTok
Twitter
YouTube

Weeks

Scratch
C
Arrays
Algorithms
Memory
Data Structures
Python
SQL
HTML, CSS, JavaScript
Flask
Ethics