> For the complete documentation index, see [llms.txt](https://wiki.songer.pro/interviewing/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.songer.pro/interviewing/security-domains-and-technical-aptitude/network-security/dns/what-is-ptr-record.md).

# 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.