If you are a specialist in cryptography, it is crucial to understand the difference between them. Otherwise, it is okay that you consider them as equal. A password is what you need to login into an account, a cipher is a series of code that keeps a piece of information from being seen by unauthorized individuals. A password is manually set by a user, while a cipher is generated by an algorithm, e.g. DES, IDEA, RSA, etc. In China, it is common that people confuse these two concepts. The correct Chinese translation of "password" is "口令", rather than “密码”, the latter is the correct Chinese translation of "cipher". Having little knowledge about cryptography, many Chinese people believe they enter "密码" when they login into their accounts, but in fact, it's "口令" or "password".