# What is PTR Record?

PTR (Pointer) records are resource records in the Domain Name System (DNS) used to provide a domain name that corresponds to an IP address. PTR records are also called Reverse DNS records because they allow a DNS server to look up an IP address and return the corresponding domain name. They are used mainly for email servers to ensure that email is sent from a legitimate source.


---

# 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://wiki.songer.pro/interviewing/security-domains-and-technical-aptitude/network-security/dns/what-is-ptr-record.md?ask=<question>
```

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.