Hello! Some of you may remember me as the person who completed every certificate on FreeCodeCamp. Well, it took me another year to do, but I've now completed every CS50 certificate. Most people probably only know the big CS50/CS50x (Introduction to Computer Science) course, but they actually offer 11 different courses. I've done them all! So here is a mini-review of each...

CS50x (Harvard's Introduction to Computer Science)

This is the CS50 course that everyone knows and loves. Taught by Prof. David Malan, you learn some Scratch, C, Python, SQL, HTML, CSS, JavaScript, and Flask. But, really, it’s about learning computer science basics and learning how to learn - the idea is that, by the end of this course, you will be able to pick up whatever programming languages or technology you need when you need it. Prof. Malan is an amazingly energetic lecturer, and the production quality is very high. To get the certificate, you need to complete 10 problem sets and build a final project.

One thing that I always careful to warn people about: it is a very difficult class for beginners. It’s an intro level class in the sense that it doesn’t assume you have any prior computer science/programming knowledge. But the learning curve for this course is extremely steep. So, personally, I don’t typically recommend this course for total beginners.

Otherwise, it’s an amazing course, and if you’re learning coding/programming/comp sci, you should absolutely put CS50x on your list.

Difficulty: Hard

CS50P (Intro to Programming with Python)

Whereas CS50x is really focused on general computer science concepts, CS50P really just focuses on learning Python. Again, this course is taught by Prof. David Malan, so the lectures are all great. Not quite as high production value as the big CS50x course, but still pretty good.

For the certificate, you need to complete 9 problem sets and build a final project. This course is challenging, but still easier than CS50x. So, for that reason, I tend to recommend completing this one first. And if you’re planning on taking CS50W or CS50AI, then this is definitely worthwhile just to hone your Python skills a bit more before those more difficult courses.

Difficulty: Medium

CS50T (Introduction to Technology)

I mostly took this course out of curiosity, as I didn’t really know what to expect from it. But I also took it because it is another course taught by Prof. David Malan, and he’s a good enough lecturer to make anything interesting. It’s described as a course “for students who don’t (yet) consider themselves computer persons.” So I almost expected it to be like, ‘here’s how to troubleshoot your printer,’ but it isn’t that basic. It’s just a version of CS50x that goes very, very light on coding. There is some Scratch and some HTML/CSS, but nothing too complicated.

It’s a short course with only 6 assignments to complete, which mostly consist of short-answer questions. So it’s like CS50x for people that don’t want to code.

Difficulty: Easy

CS50W (Web Development with Python)

Web development is my main interest, so this was the course I was most interested in taking. It’s taught Brian Yu, who has a different lecturing style than Prof. Malan, but I’d say he is also luckily a very good lecturer. He’s very good at explaining concepts.

CS50W is intended to be a follow-up to the CS50x course which focuses on building full stack applications with Django. If you didn’t have too much trouble with Flask in CS50x, then I don’t think you’ll have too much trouble here, but if you’re not super comfortable with Python, HTML, CSS, and JavaScript, then it will be a big challenge.

There are five assignments to complete, plus a final project. That may not seem like much, but the assignments are quite in depth and will take a good chunk of time to complete. I really enjoyed this course, and though I didn’t love Django at the beginning, it definitely grew on me.

Difficulty: Hard

CS50SQL (Intro to Databases with SQL)

As you may have guessed, this course focuses on building and querying databases using SQL. I don’t think SQL is the most exciting language, but since so much of the software world is about CRUD, this is a course I’d recommend to most people. And, luckily, this one is taught by Carter Zenke who is another good lecturer (and I believe he is also teaching the forthcoming CS50R)

Completing this course requires submitting 7 problem sets and a final project. And, honestly, I had fun doing it all.

Difficulty: Medium

CS50CS (Intro to Cybersecurity)

This newest course from CS50, and I would describe it as a broad overview of a bunch of different cybersecurity topics. You never get too in-the-weeds on any given topic, and there is no coding involved here (you’re not going to be programming a port sniffer in Python or anything like that). So it really does work as a good introductory course.

This course is once again taught by Prof. David Malan, who is as good as always. And it’s one of the shorter courses as well. To get the certificate, you need to submit 5 assignments (like CS50T, each assignment is mostly a bunch of short-answer questions) and a final project. The final project here is interesting: you have to find a recent cybersecurity incident in the news and record a ~10 minute presentation on it.

Difficulty: Easy

CS50B (CS50 for Business Professionals)

This one is very similar to CS50T, just with some modifications to aim it more towards a business-minded audience. Taught again by David Malan, it covers a lot of the same concepts as CS50x but without much of the programming (you only have to deal with a bit of HTML/CSS and Scratch).

There are six assignments, and they are each mostly just a collection of short-answer questions. If you’ve done CS50x this will be an absolute breeze. If this is your first computer science course, you’ll be more challenged, but I don’t think it’s too difficult overall.

Difficulty: Easy

CS50AI (Intro to AI with Python)

This is another follow-up course to CS50x taught by Brian Yu, and it is easily the most difficult course that CS50 offers. The course covers everything from (relatively) simple search algorithms to modern LLMs, and luckily Brian has a way of explaining everything in a very intuitive way. In the lectures, he really focuses on the concepts, to the point that it often feels like you’re hardly seeing any code at all.

To complete the course, you have to submit 7 quizzes - these are all multiple choice and not too difficult - and twelve assignments. These assignments are where it gets difficult. It is a very algorithm heavy course, and I often found myself banging my head against the keyboard for hours trying to get things to work.

I really muddled my way through this course. Even though it was a rewarding experience, it was so difficult at times that I was quite happy for it to be over.

Difficulty: Very Hard

CS50S (Intro to Programming with Scratch)

People often look down on Scratch because it’s a programming language designed for kids, but I honestly had a total blast with this one. It’s taught by Brian Yu, and the lectures are quite short (usually around 30 minutes). If you have some programming experience, you won’t have much trouble with this course at all.

There are 8 assignments, many of which are quite simple, and a final project. I tried to do clever or unique things with Scratch, and I really had fun making weird mini-games. If you’re thinking about taking CS50G, then I think CS50S would be a good warm up.

Difficulty: Easy

CS50L (CS50 for Lawyers)

With this course, I was expecting something similar to CS50T and CS50B (a light version of CS50x). However, it’s definitely more challenging than I’d anticipated.

It’s a longer course, and requires completing 10 assignments (each one mostly being short-answer type questions). The course covers general computer science topics covered in CS50x plus some lectures on cryptography, cybersecurity, and tech-related legal issues. It also covers a bit of Scratch, HTML, CSS, JavaScript, and Python. If you’ve done CS50x already, this won’t be too difficult, but it’s definitely going to be a challenge for anyone who hasn’t done programming/coding.

This one is co-taught by David Malan and Doug Lloyd (who provides the legal perspective).

Difficulty: Medium

CS50G (Intro to Game Development)

Out of all the CS50 courses, this one is in most need of updating. It teaches LOVE2D (uses Lua) and Unity (uses C#), both of which have had big-ish updates since this course was released. But if you’re here to learn more about game dev concepts, then it’s mostly still relevant.

It’s taught by Colton Ogden. In contrast to a lecturer like Brian Yu who really focuses on the conceptual aspects, you spend a lot of time with Colton just going through code.

There are 11 assignments, which are all essentially “take this game that Colton built and add some extra features.” Some of the assignments were easy and took very little time, but many took hours and hours to implement. The hardest thing in my experience was just understanding the codebase. For a couple of the assignments I just jumped right in without taking the time to look through the codebase, and I suffered for it.

There is also a final project that requires you to create a whole new game. This is, for obvious reasons, quite time consuming and difficult. I was quite exhausted by the end of this course, and it made me realize that I probably never want to do any game development ever again. Though, I definitely have a newfound appreciation for video games.

Difficulty: Very Hard