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    Main content
    Computing

    Computer science

    Learn select topics from computer science - algorithms (how we solve common problems in computer science and measure the efficiency of our solutions), cryptography (how we protect secret information), and information theory (how we encode and compress information).
    My Projects Help Requests
    Project Evaluations Community Questions
    Did you know? You can learn how to program on Khan Academy and create your own programs. Go to our computer programming subject to get started.

    Algorithms

    We've partnered with Dartmouth college professors Tom Cormen and Devin Balkcom to teach introductory computer science algorithms, including searching, sorting, recursion, and graph theory. Learn with a combination of articles, visualizations, quizzes, and coding challenges.

    Journey into cryptography

    How have humans protected their secret messages through history? What has changed today?

    Journey into information theory

    We've always been communicating.... as we moved from signal fires, to alphabets & electricity the problems remained the same.

    Internet 101

    Thanks to our partners at Code.org, you can learn how the internet works - everything from WiFi and IP addresses to cybersecurity and crime.
    Computer science

    Journey into information theory

    We've always been communicating.... as we moved from signal fires, to alphabets & electricity the problems remained the same.
    Community Questions
    All content in “Journey into information theory”

    Ancient information theory

    Explore the history of communication from signal fires to the Information Age
    • What is information theory? (Video)
    • Origins of written language (Video)
    • History of the alphabet (Video)
    • Ptolemaic: Rosetta Stone (Video)
    • Source encoding (Video)
    • Visual telegraphs (case study) (Video)
    • Decision tree exploration (Scratchpad)
    • Electrostatic telegraphs (case study) (Video)
    • The battery and electromagnetism (Video)
    • Morse code and the information age (Video)
    • Morse code Exploration (Scratchpad)

    Modern information theory

    Information Theory in the 20th Century
    • Symbol rate (Video)
    • Introduction to channel capacity (Video)
    • Message space exploration (Scratchpad)
    • Measuring information (Video)
    • Origin of Markov chains (Video)
    • Markov chain exploration (Scratchpad)
    • A mathematical theory of communication (Video)
    • Markov text exploration (Scratchpad)
    • Information entropy (Video)
    • Compression codes (Video)
    • Error correction (Video)
    • The search for extraterrestrial intelligence (Video)