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The Most Popular Intro to Programming Course From Harvard is Free!

CS50's Introduction to Computer Science has the highest enrollment on Harvard's campus... and is free to anyone interested in taking it!

The Most Popular Intro to Programming Course From Harvard is Free!

If you are interested in pursuing one of the best jobs in America, it involves learning and understanding Computer Science.

Harvard University, one of the top schools in the world offers popular programming courses called CS50 and gives you the basics of Computer Science. The courses are done through the e-learning platform edX, which is co-founded by Harvard. These courses are free to enroll, however, there is a chance to pay a fee to receive a certificate, which you can add to your resume or LinkedIn.

CS50 courses are very popular and have benefitted people who have no Computer Science experience to people who know how to program. On the 7th of December 2005, Mark Zuckerberg joined CS50 with Professor Michael D. Smith for a guest lecture about Facebook and computer science. 

CS50 is currently Harvard's largest course with 3,493,337 already enrolled. 


CS50's Introduction to Computer Science

CS50's Introduction to Computer Science has the highest enrollment on Harvard's campus and is one of edX top 100 courses of all time. It is taught by David J. Malan, Doug Lloyd, and Brian Yu, and is Harvard’s largest course. 

  • Course Language: English
  • How long is the course? Estimated 12 weeks, 6–18 hours per week
  • Difficulty level? Introductory
  • Cost: Free, Verified Certificate for $149. Students who earn a satisfactory score on 9 problem sets and the final project are eligible for a certificate.
  • edx Link: CS50's Introduction to Computer Science
  • Youtube Link: CS50's Introduction to Computer Science
  • GitHub Link: CS50
  • Discord Link: https://discord.gg/T8QZqRx
  • Twitter:https://twitter.com/cs50


    Course Breakdown


    Lecture 0 - Scratch

    This is week 0 of CS50, where you will learn about the fundamentals of computer science, and how we can use it to solve problems. It dives into the representation of numbers, for example, decimal and binary, aswell as the ASCII character encoding for Text. 

    Other topics include Images, video, sounds, how algorithms are used to solve problems, and how to write pseudocode. Your first understanding of programming will be using a graphical programming language called Scratch, exploring abstraction and conditionals. 


    Lecture 1 - C

    This is week 1 of CS50, where you will be learning the programming language, C. You will dive into popular IDEs such as Visual Studio Code along with grasping compilers and interfaces.

    You will then further go into topics such as functions, arguments, return values, variables, and learning new commands. Other topics included in this lecture are types, format codes, operators, conditionals, boolean expressions, loops, and more. 


    Lecture 2 - Arrays

    This is week 2 of CS50. At this point, you would have understood the basic concept of Computer Science and how to use the programming language C to return values, do a loop, and understand the types of data that you could come across. 

    The topics included in this lecture are compiling, debugging, memory, arrays, characters, strings, command-line arguments, and applications by printing “hello, world”, your name, and more within each of these topics to give you a clearer understanding. 


    Lecture 3 - Algorithms

    This is week 3 of CS50, and you will be learning about Algorithms. In this lecture, you will use all the fundamentals and tools of solving a problem from the previous lecture and imbed them into how algorithms solve problems with arrays.

    Topics included are Linear/binary search, searching using code, struct, sorting and selecting data, recursion, and merge sort. These topics will help you appreciate how algorithms can be used to solve a lot of simple problems. 


    Lecture 4 - Memory

    This is week 4 of CS50, where you would have vaguely gone over memory and how arrays are used to store data. This lecture further explores the granulated understanding of the storage of data. 

    Topics included in this lecture are pixels, hexadecimal, addresses, pointers, strings, pointer arithmetic, memory allocation, garbage values, files, JPEG, and more. The visual representation of each topic helps you understand the concept of each and how data is stored. 


    Lecture 5 - Data Structures

    This is week 5 of CS50, and in this lecture, you will understand more about Data Structures and the different types. This lecture focuses on arrays and memory, and how you can allocate more memory and move the array.

    Topics include recap, linked lists, growing arrays, growing linked lists, implementing linked lists, trees, and more about data structures.


    Lecture 6 - Python

    This is week 6 of CS50, and you will be learning a new programming language: Python! It will go through the similarities between C and Python using previous examples. 

    Therefore, the topics are similar to Lecture 1 - C however has a few more. These include python syntax, libraries, input, conditions, documentation, lists, strings, command-line arguments, exit codes, algorithms, files, and more libraries.


    Lecture 7 - SQL

    This is week 7 of CS50, and it primarily focuses on SQL which is a popular standardized programming language used to manage relational databases and perform operations on the data within the database.

    Topics you will cover include different file types, data cleaning, relational databases, SQL and its functionalities, SQLite, primary/foreign key, and more. SQL is a very popular programming language and is much easier to learn than SQL. 


    Lecture 8 - HTML, CSS, JavaScript

    This is week 8 of CS50, and you will be learning more programming languages. HTML, CSS, and JavaScript work hand-in-hand. HTML provides the basic structure for a website, CSS controls the presentation, formatting, and layout of a website, whilst JavaScript controls the behavior of different elements.

    You will learn everything about the internet and websites, for example, routers, IP Addresses, HTTP,  URL Parameters, HTML, CSS, and JavaScript elements. 



    This lecture is not particularly a part of Computer Science; however, it is an important element of technology as a whole. This dives into ways to keep your computer, laptop, data, and phone secure. 

    Topics included in this lecture are passcodes, Brute-Force attacks, Two-Factor Authentication, password managers, and encryption.


    Lecture 9 - Flask

    This is week 9 of CS50, and in this lecture, you will learn about Flask which is a micro web framework written in Python that provides useful tools to create a web application.

    You will learn about web servers, templates, layouts, error checking, storing data, databases, and more. 


    Artificial Intelligence

    As the lecture on Security, this lecture is also not a part of the CS50 syllabus, however, it is important to know more about Artificial Intelligence and how it is used. Artificial Intelligence is one of the reasons why there is an increased demand for Data Scientists. 

    Topics include decision-making, decision trees, heuristics, reinforcement learning, neural networks, and more. 


    Lecture 10 - Ethics

    This is week 10 of CS50, the last lecture of the course. This lecture will go over the tools and skills you have learned and how you can continue to grow and implement them. It will also go over computational thinking as well as the ethics behind overall technology. 


    A summary of what you will learn


    • This is an entry-level course that teaches and guides students to use a sequence of steps using programming to solve a specific problem efficiently. 
    • Understanding programming languages such as C, Python, SQL, JavaScript, CSS, and HTML. 
    • Topics include abstraction, algorithms, data structures, encapsulation, resource management, security, software engineering, and web development.
    • Real-world problems such as finance forensics, cryptography, and gaming.

    Nisha Arya is a Data Scientist and Freelance Technical Writer. She is particularly interested in providing Data Science career advice or tutorials and theory based knowledge around Data Science. She also wishes to explore the different ways Artificial Intelligence is/can benefit the longevity of human life. A keen learner, seeking to broaden her tech knowledge and writing skills, whilst helping guide others.