The Quantum Internet is emerging as a new networking paradigm in which quantum communication technologies complement the classical Internet rather than replace it. Its goal is to enable distributed quantum devices to exploit uniquely quantum resources such as superposition and entanglement, supporting applications including quantum key distribution, distributed quantum computing, secure cloud quantum computing, and distributed sensing.

This tutorial provides a networking-oriented introduction to the fundamental concepts required to understand how a Quantum Internet can operate. No previous background in quantum mechanics is assumed. Starting from the quantum bit, the tutorial introduces superposition, measurement, entanglement, Bell pairs, and the no-cloning theorem, emphasizing their consequences for communication networks. It then presents the two key primitives of quantum networking: quantum teleportation, which enables the transfer of an unknown quantum state using a previously distributed Bell pair and classical communication, and entanglement swapping, which allows entanglement to be extended over multiple network hops through quantum repeaters.

The tutorial subsequently introduces fidelity as a fundamental measure of the quality of distributed entanglement and briefly discusses error-management mechanisms such as entanglement distillation. Finally, the focus moves to the architecture of the Quantum Internet, highlighting the fundamental differences with classical networking: Bell pairs rather than packets become the main network resource, quantum and classical communication must coexist, and the traditional store-and-forward paradigm is complemented by a store-and-swap model based on entanglement generation, storage, and swapping.

The tutorial concludes with an overview of open research challenges, including entanglement routing and scheduling, fidelity-aware resource allocation, quantum-memory constraints, coordination between classical and quantum data planes, and support for heterogeneous quantum technologies.