以光子的偏振态为例，对量子力学、量子态、量子密码、量子纠缠和量子隐形传态作简要通俗而又力求准确的介绍。首先通过与经典物理的对比，引进量子力学的基本思想和量子态的基本涵义；接着介绍量子密码的BB84量子密钥分配方案；然后介绍量子纠缠，强调它不违反相对论。在此基础上，介绍了量子隐形传态，强调了经典通信在这个过程中的必不可少。

Exemplified by the polarized states of photons, we make a concise, accurate and easily comprehensible introduction to the concepts of quantum mechanics, quantum states, quantum cryptography, quantum entanglement and quantum teleportation. First, the fundamental ideas of quantum mechanics and the meaning of quantum states are introduced through the comparison with classical physics. Then the BB84 scheme of quantum key distribution in quantum cryptography is explained. Afterwards, the concept of quantum entanglement is introduced, with the emphasis that it does not violate the theory of relativity. On the basis of this, quantum teleportation is explained, with the necessity of classical communication in the process emphasized.