CS50 Fall 2025 - Lecture 0 - Scratch (live, unedited)

*** This is CS50, Harvard University's introduction to the intellectual enterprises of computer science and the art of programming. *** TABLE OF CONTENTS 00:18:01 - Introduction 00:19:32 - This is CS50 00:19:53 - Artificial Intelligence 00:31:39 - Computer Science 00:32:48 - Unary 00:34:58 - Binary 00:47:18 - ASCII 00:58:24 - Unicode 01:02:30 - Color 01:07:54 - Representation 01:13:04 - Algorithms 01:22:20 - Pseudocode 01:31:49 - Scratch 01:35:55 - Hello, World 01:38:40 - Hello, You 01:48:01 - Meow 01:51:32 - Abstractions 01:55:24 - Conditionals 01:57:46 - Oscartime 02:09:28 - Ivy’s Hardest Game *** HOW TO SUBSCRIBE http://www.youtube.com/subscription_center?add_user=cs50tv HOW TO TAKE CS50 edX: https://cs50.edx.org/ Harvard Extension School: https://cs50.harvard.edu/extension Harvard Summer School: https://cs50.harvard.edu/summer OpenCourseWare: https://cs50.harvard.edu/x HOW TO JOIN CS50 COMMUNITIES Bluesky: https://bsky.app/profile/cs50.harvard.edu Discord: https://discord.gg/cs50 Ed: https://cs50.edx.org/ed Facebook Group: https://www.facebook.com/groups/cs50/ Faceboook Page: https://www.facebook.com/cs50/ GitHub: https://github.com/cs50 Gitter: https://gitter.im/cs50/x Instagram: https://instagram.com/cs50 LinkedIn Group: https://www.linkedin.com/groups/7437240/ LinkedIn Page: https://www.linkedin.com/school/cs50/ Medium: https://cs50.medium.com/ Quora: https://www.quora.com/topic/CS50 Reddit: https://www.reddit.com/r/cs50/ Slack: https://cs50.edx.org/slack Snapchat: https://www.snapchat.com/add/cs50 SoundCloud: https://soundcloud.com/cs50 Stack Exchange: https://cs50.stackexchange.com/ Telegram: https://t.me/cs50x Threads: https://www.threads.net/@cs50 TikTok: https://www.tiktok.com/@cs50 Twitter: https://twitter.com/cs50 Twitter Community: https://twitter.com/i/communities/1722308663522594923 YouTube: http://www.youtube.com/cs50 HOW TO FOLLOW DAVID J. MALAN Facebook: https://www.facebook.com/dmalan GitHub: https://github.com/dmalan Instagram: https://www.instagram.com/davidjmalan/ LinkedIn: https://www.linkedin.com/in/malan/ Quora: https://www.quora.com/profile/David-J-Malan Threads: https://www.threads.net/@davidjmalan TikTok: https://www.tiktok.com/@davidjmalan Twitter: https://twitter.com/davidjmalan *** CS50 SHOP https://cs50.harvardshop.com/ *** LICENSE CC BY-NC-SA 4.0 Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International Public License https://creativecommons.org/licenses/by-nc-sa/4.0/ David J. Malan https://cs.harvard.edu/malan [email protected]