DNS records are called mapping files. When a web server sends a request by a user to visit a particular website, the request is sent to the DNS database. This database looks up its records, finds the website's IP address and forwards it to the requesting server. After getting this information, the requesting server uses the IP address to find the website and display it to the user who initiated the request.
There are letters associated with the DNS records which are known as DNS syntax. Some of the commonly used syntax with all DNS records are; A, AAAA, CNAME, MX, PTR, NS, SOA, SRV, TXT and NAPTR.
The A syntax in a DNS record is the most basic type of syntax. It stands for address and indicates the IP address of the website.
The AAAA record is an IPV6 address which maps the hostname to a 128-bit IPV6 address.
The CNAME stands for conical name and is used to associate sub domains with existing DNS records.
The MX stands for mail exchange and is used for mail exchange servers.
The PTR record as the name indicates a pointer record and maps an IPV4 address to the CNAME.
The NS record stands for name server and indicates the server on which the domain resides.
The SOA record stores important information about the domain, like when was it last updated.
The SRV record indicates which TCP service the domain operates.
The TXT record permits the website's administrator to insert any text in the record.