CS50's Introduction to Computer Science from edX

This is CS50x , Harvard University's introduction to the intellectual enterprises of computer science and the art of programming for majors and non-majors alike, with or without prior programming experience. An entry-level course taught by David J. Malan, CS50x teaches students how to think algorithmically and solve problems efficiently. Topics include abstraction, algorithms, data structures, encapsulation, resource management, security, software engineering, and web development. Languages include C, Python, SQL, and JavaScript plus CSS and HTML. Problem sets inspired by real-world domains of biology, cryptography, finance, forensics, and gaming. The on-campus version of CS50x , CS50, is Harvard's largest course.

Students who earn a satisfactory score on 9 problem sets (i.e., programming assignments) and a final project are eligible for a certificate. This is a self-paced course–you may take CS50x on your own schedule.

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What's inside

Learning objectives

A broad and robust understanding of computer science and programming
How to think algorithmically and solve programming problems efficiently
Concepts like abstraction, algorithms, data structures, encapsulation, resource management, security, software engineering, and web development

Familiarity in a number of languages, including c, python, sql, and javascript plus css and html
How to engage with a vibrant community of like-minded learners from all levels of experience
How to develop and present a final programming project to your peers

A broad and robust understanding of computer science and programming
How to think algorithmically and solve programming problems efficiently
Concepts like abstraction, algorithms, data structures, encapsulation, resource management, security, software engineering, and web development
Familiarity in a number of languages, including c, python, sql, and javascript plus css and html
How to engage with a vibrant community of like-minded learners from all levels of experience
How to develop and present a final programming project to your peers

Good to know

Know what's good

, what to watch for

, and possible dealbreakers

Designed for individuals with and without programming experience, explicitly addressing non-majors as well as majors

Taught by David J. Malan, Doug Lloyd, and Brian Yu, recognized educators and practitioners in the field

Emphasizes the application of computer science concepts in various real-world domains, fostering practical problem-solving abilities

Involves hands-on experience through programming assignments and a final project, allowing learners to apply their knowledge and receive feedback

Offers a comprehensive introduction to computer science, encompassing foundational concepts and programming languages

Engages learners in a vibrant online community, fostering collaboration and peer support

Activities

Be better prepared before your course. Deepen your understanding during and after it. Supplement your coursework and achieve mastery of the topics covered in CS50's Introduction to Computer Science with these activities:

Review Basic Programming Concepts

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Strengthen your programming foundation by reviewing basic concepts such as variables, data types, control flow, and operators to ensure you are well-prepared for the course material.

Browse courses on Programming Fundamentals

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Go through your previous programming notes or textbooks.
Complete online tutorials or exercises on basic programming concepts.
Practice writing simple programs to reinforce your understanding.

Organize and Review Course Materials

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Make the most of your course materials by compiling and organizing your notes, assignments, quizzes, and exams. This will help you stay organized, review effectively, and improve your retention of the material.

Browse courses on Study Skills

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Gather all of your course materials, including notes, assignments, and exams.
Create a system for organizing your materials, such as using folders or a digital note-taking app.
Review your materials regularly and identify areas where you need further understanding.

Form a Study Group with Classmates

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Enhance your learning by forming a study group with classmates where you can discuss concepts, work on assignments together, and provide support to each other.

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Identify classmates who share your interests and learning goals.
Establish regular meeting times and a designated study space.
Set clear goals for each study session and divide tasks among group members.

Four other activities

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Attend a Workshop on Web Development

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Expand your knowledge and skills in web development by attending a workshop that covers topics such as HTML, CSS, JavaScript, or back-end technologies.

Browse courses on Web Development

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Research different workshops and choose one that aligns with your interests and learning goals.
Register for the workshop and prepare any necessary materials.
Attend the workshop, participate actively, and take notes.

Solve Coding Challenges on LeetCode

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Sharpen your problem-solving skills and reinforce your understanding of algorithms and data structures by practicing coding challenges on LeetCode.

Browse courses on Algorithms

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Choose a coding challenge that is appropriate for your skill level.
Attempt to solve the challenge on your own.
Review the optimal solution and compare it to your approach.

Build a simple text editor

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Enhance your understanding of user interface design, front-end development, and programming fundamentals by creating a basic text editor that enables you to type and edit text.

Browse courses on Text Editor

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Design the user interface for your text editor.
Implement the core functionality for text editing, such as typing, deleting, and copying.
Add features to your text editor, such as syntax highlighting or spell checking.

Build a Personal Portfolio Website

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Showcase your skills and projects by building a personal portfolio website that demonstrates your proficiency in web development and provides a platform for you to present your work.

Browse courses on Web Development

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Design the layout and structure of your website.
Develop the front-end of your website using HTML, CSS, and JavaScript.
Create a back-end for your website if necessary, using a server-side language.

Career center

Learners who complete CS50's Introduction to Computer Science will develop knowledge and skills that may be useful to these careers:

Computer Scientist

Computer Scientists are problem solvers. They analyze problems, turn them into a set of instructions, then have computers perform the instructions. This course can help you gain a broad understanding of computer science, as well as how to think algorithmically and solve programming problems efficiently. It can also expose you to a variety of programming languages, include C, Python, SQL, and JavaScript, which many Computer Scientists use to solve problems in a diverse range areas, such as finance, forensics, data science, government, healthcare, and more. While the course description does not specifically list the role of Computer Scientist, its broad overview of computer science and programming can lay a foundation for careers in this field.

See salaries and explore the career path for Computer Scientist

Computer Science Teacher

Computer Science Teachers educate students about computer science principles and concepts. They teach students how to think algorithmically and solve problems efficiently. This course can provide you with a broad understanding of computer science, as well as how to think algorithmically and solve programming problems efficiently. While the course description does not specifically list the role of Computer Science Teacher, its broad overview of computer science and programming can lay a foundation for careers in this field.

See salaries and explore the career path for Computer Science Teacher

Web Developer

Web Developers design and build websites. They are responsible for the look, feel, and functionality of websites. This course provides a solid foundation in computer science principles, including web development concepts. You will learn about topics like HTML, CSS, and JavaScript, which are essential for Web Developers. This course may also be useful if you are interested in becoming a Web Developer because it will expose you to the fundamentals of computer science and help you gain experience in some important programming languages.

See salaries and explore the career path for Web Developer

Database Administrator

Database Administrators are responsible for the performance, security, and maintenance of databases. This course provides a solid foundation in computer science principles, including database management concepts, which are essential for Database Administrators. You will also gain experience working with SQL, a programming language commonly used by Database Administrators to manage and query data.

See salaries and explore the career path for Database Administrator

Data Analyst

Data Analysts collect, clean, and analyze data to help businesses make informed decisions. This course provides a solid foundation in computer science principles, including data structures and algorithms, which are essential for Data Analysts. It also provides hands-on experience working with data using SQL, a programming language commonly used by Data Analysts to manipulate and query data.

See salaries and explore the career path for Data Analyst

Computer Systems Analyst

Computer Systems Analysts analyze and design computer systems to meet the needs of businesses. They work with users to identify their needs, then design and implement systems to meet those needs. This course will provide you with a foundation in computer science principles, including systems analysis and design, which are essential for Computer Systems Analysts. It also covers a variety of programming languages, including C, Python, SQL, and JavaScript, which Computer Systems Analysts often use to develop and implement computer systems.

See salaries and explore the career path for Computer Systems Analyst

Information Systems Manager

Information Systems Managers plan, implement, and manage information systems for organizations. They work with users to identify their needs, then design and implement systems to meet those needs. This course will provide you with a foundation in computer science principles, including systems analysis and design, which are essential for Information Systems Managers. It also covers a variety of programming languages, including C, Python, SQL, and JavaScript, which Information Systems Managers often use to develop and implement information systems.

See salaries and explore the career path for Information Systems Manager

Systems Analyst

Systems Analysts design and implement computer systems that meet the needs of businesses. They analyze business processes, identify areas for improvement, and then design and implement systems to address those needs. This course will provide you with foundation in many computer science principles, including systems analysis and design, which are essential for Systems Analysts. It also covers a variety of programming languages, including C, Python, SQL, and JavaScript, which Systems Analysts often use to develop and implement computer systems.

See salaries and explore the career path for Systems Analyst

Information Security Analyst

Information Security Analysts plan and implement security measures to protect computer systems and networks from unauthorized access, use, disclosure, disruption, modification, or destruction. This course will give you a broad overview of computer science principles, including security concepts, which are essential for Information Security Analysts. You will also learn about a variety of programming languages, such as C, Python, SQL, and JavaScript. Many of these languages are used by Information Security Analysts to develop and implement security measures.

See salaries and explore the career path for Information Security Analyst

Software Engineer

Software Engineers apply the principles of computer science to design, develop, deploy, and maintain software systems. This course is a great introduction to the fundamentals of computer science. It teaches you how to think algorithmically and solve problems efficiently. You will also gain experience in a number of popular programming languages like C, Python, SQL, and JavaScript. As a Software Engineer, you need to be able to work with many programming languages and understand a variety of different computer science principles, so the broad overview of this course may be very helpful. While the course description does not state the role of Software Engineer specifically, it may help you build a foundation for a career in this field.

See salaries and explore the career path for Software Engineer

IT Project Manager

IT Project Managers plan, execute, and close IT projects. They work with stakeholders to define project scope, develop project plans, and manage project resources. This course will provide you with a foundation in computer science principles, including project management concepts, which are essential for IT Project Managers. It also covers a variety of programming languages, such as C, Python, SQL, and JavaScript, which IT Project Managers often use to develop and implement IT projects.

See salaries and explore the career path for IT Project Manager

Network Administrator

Network Administrators are responsible for the performance, security, and maintenance of computer networks. This course provides a solid foundation in computer science principles, including network management concepts, which are essential for Network Administrators. You will also gain experience working with a variety of programming languages, such as C, Python, SQL, and JavaScript, which Network Administrators often use to manage and maintain networks.

See salaries and explore the career path for Network Administrator

Data Scientist

Data Scientists use their knowledge of computer science, statistics, and mathematics to extract insights from data. This course will provide you with a solid foundation in computer science principles, as well as experience working with data using SQL, a programming language that Data Scientists use to manipulate and query data. While the course description does not specifically mention the role of Data Scientist, the course may be helpful as it will introduce you to fundamental computer science concepts and data analysis techniques.

See salaries and explore the career path for Data Scientist

Computer Programmer

Computer Programmers write and maintain the code that makes computers work. They turn ideas into reality by translating designs and specifications into instructions that computers can understand. While the course does not discuss this role specifically, it covers a number of essential programming concepts and gives students experience in various programming languages, including C, Python, SQL, and JavaScript, which may be attractive to potential employers.

See salaries and explore the career path for Computer Programmer

Software Tester

Software Testers evaluate the functionality of software applications to identify and report bugs. This course will provide you with a foundation in computer science principles, including software testing concepts, which are essential for Software Testers. It also covers a variety of programming languages, including C, Python, SQL, and JavaScript, which Software Testers often use to develop and implement test cases.

See salaries and explore the career path for Software Tester