Harvard CS 50x — Week 0 (Scratch)

We’re officially a week into September! 🍁🍂
Can you believe it’s been 6 months since the beginning of lockdown here in the UK? 😱

To be honest, it’s been difficult for me to find the motivation to learn outside of working hours.

But I miss learning…
So enough is enough! 🤓

I want to challenge myself by taking Havard University’s Intro to Computer Science course - CS50x. It’s basically a Computer Science introductory course, targeted at people who did not major in CS (i.e. → me!)

This year due to COVID-19, they took the course online.

After every lecture, I will:

  • write up a quick summary of bullet points
  • share my thoughts/feelings
  • link any relevant assignments that I’ve completed

Hopefully, you’ll find this intriguing!

Summary - Week 0

  • The art of problem-solving
  • Explaining why computers count in binary (base 2)
  • 0 and 1 => bits (binary digits)
  • Counting with light bulbs to represent 0 and 1
  • Binary — 2 to the power of
  • Assign numbers to letters and using bits to represent letters (a.k.a ASCII)
  • We used to use 7 bits (cause it used to be more expensive) but now 8
  • 72 73 33 = Hi!
  • Bytes is a pattern of 0s and 1s
  • Assign numbers to colours
  • Algorithms for find functions
  • Pseudocode
  • Scratch
  • Concept of D.R.Y (Don’t Repeat Yourself)
  • Usage of Loops
  • If/ Else Statements + Conditionals
  • Audio/Video/Click Events that trigger further actions
  • Abstraction

Thoughts & Feelings

It was fun, engaging, informative, and super collaborative.


  • David J. Malan is such a pleasure to learn from
  • The lecture was held over Zoom, but students can also watch via YouTube Live Stream and Facebook
  • Ability to vote in polls/answer questions/write comments to engage with the community
  • Break-down of larger and more complex structures and ideas made it so easy and simple to understand
  • Scratch is SO FUN!! (spoiler alert: cats were involved)
  • The raining men ending Scratch video was a winner


None so far!

Links to Assignments

This week we were asked to create our very own Scratch project as per this specification.

So, here is my Scratch project called “Fill Your Belly!”. Experience what it’s like to devour some delicious food in Japan.

Welcome screen to “Fill Your Belly!”

If you played the game, let me know what you think in the comments below - and as always if you found this article helpful/interesting, please do give some claps!



Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store