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Approx. 3 months
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$150 /month
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Class Summary

In this introductory course, you’ll learn and practice key computer science concepts by building your own versions of popular web applications. You’ll learn Python, a powerful, easy-to-learn, and widely used programming language, and you’ll explore fundamental computer science concepts, as you build your own search engine and social network.

What Will I Learn?

You’ll learn the programming language Python, and you’ll explore foundational concepts in computer science. Most importantly, you’ll start thinking like a software engineer by solving interesting problems (how to build a web crawler or a social network) using computer science.

This course is a first step into the world of computer science, and whether you want to become a software engineer, or collaborate with software engineers, this course is for you. You’ll be prepared for intermediate-level computer science courses when you’ve mastered the concepts covered in this course.

Build a Search Engine:

Throughout this course, you’ll build a search engine by learning about and producing key search engine components including a crawler, an index and a page rank algorithm. As you build these pieces, you’ll be learning about and practicing computer science skills that will ready you for intermediate level computer science courses.

Build a Social Network:

At the end of the course we will give you a set of relationships (i.e. strings of phrases like “Dave likes Andy, Kathleen and Kristy”) and you will use your new computer science skills to organize these relationships into a social network. With your new social network, you can explore relationships and gain insight into how you fit into your own social networks.

What Should I Know?

There is no prior programming knowledge needed for this course. Beginners are welcome!


Lesson 1: How to Get Started

Your first program: Extracting a link

Lesson 2: How to Repeat

Procedures, decisions (if), loops; finding all of the links on a page

Additional Lesson: How to Solve Problems

Universal techniques for solving programming problems

Lesson 3: How to Manage Data

Lists; crawling the web

Lesson 4: Responding to Queries

Complex data structures; building a reverse index to do searches; networks

Lesson 5: How Programs Run

Reasoning about cost; hash tables (Dictionary)

Lesson 6: How to Have Infinite Power

Recursive definitions; ranking search results

Lesson 7: Where to Go from Here

Past, present, and future of computing; exam

Extended Units:

Will be replaced by Intro to Object Oriented Programming

These units were not part of the original (7-lesson) course, but have been added to the course.

Lesson 8: How to Learn New Things

Tips for learning more on your own

Lesson 9: How to Manage Complexity

Modules, types, classes

Lesson 10: How to Reuse Classes


Lesson 11: Programs in the Real World

File IO, and Exceptions

Final Project: Build a Social Network


When does the course begin?

This class is self paced. You can begin whenever you like and then follow your own pace. It’s a good idea to set goals for yourself to make sure you stick with the course.

How long will the course be available?

This class will always be available!

How do I know if this course is for me?

Take a look at the “Class Summary,” “What Should I Know,” and “What Will I Learn” sections above. If you want to know more, just enroll in the course and start exploring.

Can I skip individual videos? What about entire lessons?

Yes! The point is for you to learn what YOU need (or want) to learn. If you already know something, feel free to skip ahead. If you ever find that you’re confused, you can always go back and watch something that you skipped.

What are the rules on collaboration?

Collaboration is a great way to learn. You should do it! The key is to use collaboration as a way to enhance learning, not as a way of sharing answers without understanding them.

Why are there so many questions?

Udacity classes are a little different from traditional courses. We intersperse our video segments with interactive questions. There are many reasons for including these questions: to get you thinking, to check your understanding, for fun, etc... But really, they are there to help you learn. They are NOT there to evaluate your intelligence, so try not to let them stress you out.

What should I do while I’m watching the videos?

Learn actively! You will retain more of what you learn if you take notes, draw diagrams, make notecards, and actively try to make sense of the material.

This Course is a Part of the

Course Instructors

instructor photo

Dave Evans


David Evans is a Professor of Computer Science at the University of Virginia where he teaches computer science and leads research in computer security. He is the author of an introductory computer science textbook and has won Virginia's highest award for university faculty. He has PhD, SM, and SB degrees from MIT.