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Learn Deeply Through Unplugged Computer Science and Turtle Geometry
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In order to learn something, first make sense of it
01
Data: the raw material
The word computer comes from the Latin computare, which means to calculate or add together, but computers today are more than just giant calculators. They can be a library, help us to write, find information for us, play music and even show movies. So how do they store all this information? Believe it or not, the computer uses only two things: zero and one!
02
Putting Computers to Work—Algorithms
Computers operate by following a list of instructions set for them. These instructions enable them to sort, find and send information. To do these things as quickly as possible, you need good methods for finding things in large collections of data, and for sending information through networks.
03
Telling Computers What To Do—Representing Procedures
A good programmer has to learn how to tell the computer what to do using a fixed set of instructions that are interpreted literally. The list of
instructions is the program. There are lots of different programming languages a programmer can choose to write these instructions in, but we
will be using a simple language that can be used without a computer.
04
Really hard problems—Intractability
Not much good buying a faster computer: if it were a hundred times faster it would still take millions of years; even one a million times faster would take hundreds of years. That's what you call a hard problem—one where it takes far longer than the lifetime of the fastest computer imaginable to come up with a solution!
05
Sharing secrets and fighting crime-Cryptography
You’ve heard of spies and secret agents using hidden codes or magic invisible writing to exchange messages. Well, that’s how the subject of “cryptography” started out, as the art of writing and deciphering secret codes. During the Second World War, the English built special-purpose electronic code-breaking machines and used them to crack military codes. And then computers came along and changed everything, and cryptography entered a new era.
06
The human face of computing-Interacting with computers
Computing is not so much about calculation as it is about communication. Computing per se really has no intrinsic value; it is only worthwhile if the
results are somehow communicated to the world outside the computer, and have some influence there. Perhaps surprisingly, this means that computer science is less about computers and more about people.