The qubit is the basic unit of quantum information, and nearly everything else in the course is built on it. This module explains what a qubit is, why it can hold more than a plain 0 or 1, and how to reason about it using the math from the previous module.
It starts with qubits and superposition in plain language, including how amplitudes relate to probabilities. From there it moves to the Bloch sphere, a way to picture any single-qubit state, and to measurement, where a superposition collapses to a definite outcome. It closes with a short hands-on Qiskit example that puts a qubit into superposition and measures it.
Watch the lessons in order, then continue on to Quantum Gates & Circuits.
An introduction to qubits and superposition that builds on amplitudes and probabilities, and why quantum computers work differently from classical ones.
A walkthrough of bits versus qubits, how physical objects like electron spins act as qubits, and how superposition and measurement fit together.
A more technical lecture on qubit states, the Bloch sphere, and how measurements in different bases work.
A short coding example that uses a Hadamard gate to create superposition and then measures the result in Qiskit.