# Introduction ### Domain A domain name is a string used to identify one or more IP addresses, serving as a label for a server, host, organization, or other resource on the internet. Domain names simplify the addressing system on the internet, as people find it easier to remember a domain name rather than a complex series of numbers. A domain name typically consists of multiple parts separated by periods, such as "example.com". In the domain name system, each domain name corresponds to one or more IP addresses, allowing users to access the respective server or host by using the domain name. ### Authoritative DNS Authoritative DNS refers to the resolution result provided by the domain's authoritative server during the domain name resolution process. The authoritative server stores the information of all host records for that domain. When other DNS servers query the resolution records for that domain, the authoritative server provides the authoritative resolution result. Specifically, when you enter a website address like [www.example.com](http://www.example.com/) in your browser, the local DNS server first checks its cache to see if there is a corresponding resolution record for that domain name. If it doesn't exist, the local DNS server queries the root domain server to find the top-level domain server for that domain (such as the .com top-level domain server). The top-level domain server provides the authoritative server address for that domain, and the local DNS server then queries the authoritative server for the resolution result of that domain. This result is known as authoritative resolution. ### Zenlayer DNS Zenlayer DNS is a platform that provides authoritative DNS resolution management services. On this platform, you can easily manage domain hosting and configure intelligent domain resolution. It allows you to efficiently route end-users to the best available resources, thereby significantly improving user experience for applications, streaming services, and other businesses. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://dnsdoc.routerman.ecn.zenlayer.net/introduction/introduction.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.