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A basic unit of quantum data is a “qubit” and a group of qubits together we call a “quantum register.”
Let's take a look at a single qubit.

So far, we have only talked about waves and superposition. We have another half-dozen topics to introduce in our basic concepts of quantum computing, and they are all fundamental physical concepts, independent of the desire to build a quantum computer. But if we are going to talk about computing, we need data, and it is convenient to talk about the next several concepts in terms of quantum data, so we will pause here to be somewhat quantum computer-specific. In this video, we will introduce the concept of the quantum bit, or qubit, and take our first look at how to write down its state.

Once you have seen the key concepts, in the next Step we will expand our understanding of how to write down quantum states by using several more examples, then explain a little about the mathematics. It’s okay if you don’t follow all of the math in the next Step. That will be followed by a short quiz on qubits, just to reinforce your understanding. After the quiz, we will pick up the next new major concept and study qubit measurement.




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Understanding Quantum Computers

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