护照是各主权国家颁发给本国公民出入境时使用的身份和国籍证明。自从它作为一种国。际旅行证件问世以来，得到了各国政府的普遍认可，护照制度也成为各国移民法（或称出入境管理法）的内容之一，并形成国际惯例而受到法律保护和世界各国遵守。然而，在世界各国同时也存在着制? Passports are the proof of identity and nationality used by the sovereign states when they issue their passports to and from their country of origin. Since it is a nation. Since the advent of international travel documents, it has been universally recognized by governments of all countries and the passport system has also become one of the contents of immigration laws (or immigration laws) in various countries and has become an international practice and protected by law and is complied with by all countries in the world. However, there are also systems all over the world?