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 Har…
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Chapters (20)
18:01
Introduction
19:32
This is CS50
19:53
Artificial Intelligence
31:39
Computer Science
32:48
Unary
34:58
Binary
47:18
ASCII
58:24
Unicode
1:02:30
Color
1:07:54
Representation
1:13:04
Algorithms
1:22:20
Pseudocode
1:31:49
Scratch
1:35:55
Hello, World
1:38:40
Hello, You
1:48:01
Meow
1:51:32
Abstractions
1:55:24
Conditionals
1:57:46
Oscartime
2:09:28
Ivy’s Hardest Game
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