What Does DNS Stand For? How It Works, Types & Examples

DNS stands for Domain Name System (RFC 2929). It is an internet service by which human-readable domain names (eg- www.abz.com ) are located and translated into machine-readable IP addresses (eg- 50.16.85.103). As an example, DNS may be considered as a phone directory.

When we ask what does DNS stand for, we must keep in mind that it holds crucial information about the domain names. These domain names comprise of – email servers (MX records) and email validation protocols (DKIM, SPF, DMARC), TXT record verification, and SSH fingerprints. Thus, DNS works by keeping a record of every device that accesses the internet as per their IP addresses. For example, the basic DNS definition is a server that answers to your browser what is the IP address of a domain name.

DNS definition: What does DNS stand for in networking

In terms of networking, DNS stands for Domain Name System (some may also call Domain Name Server). Both are correct DNS definitions. Whenever a user makes a visit to a website, the web browser “asks” the ISP what is the IP address of the domain name. A simple question? Yes, quite. The internet TCP/IP protocol works only by IP addresses. So, a domain name is just like a “front end” to an IP address of a server.

Certainly, the DNS system in networking is necessary to establish all the communications between servers.

What does DNS stand for in computing

In computing terms, DNS is an internet-based naming system used for converting the alphabetic names of web-based services into numerical forms, known as IP addresses. DNS naming system is used in networks operating on TCP/IP protocol. It identifies the computers and services through easy to use names.

How does DNS work?

The DNS protocol works just like querying a specific domain name for its IP address. This is called “DNS Lookup”. Whenever you try to open a URL in your web browser, it will query the DNS records for the IP address of the domain name (with a DNS Lookup).

Then, the DNS server tells your browser the IP address of the web server. And finally, the browser establishes a connection with the webserver using this IP and asks for the specific content of the file and path of the requested URL.

Above all, 99% of internet traffic is based on the TCP/IP protocol. This protocol only “talks” from IP to IP. A domain name (or a subdomain) is like a beautiful “front end” to make things easier for the customer.

For example, imagine if there weren’t DNS Servers in the world. Every store would give you a business card with their IP address just like: “185.15.43.160”.

DNS Record Types Explained

DNS records are instructions stored in DNS servers that tell the internet how to handle requests for your domain. Each record type serves a specific purpose. Here are the most common ones:

A Record (Address Record) The most basic DNS record. It maps a domain name to an IPv4 address. For example, it tells the browser that copahost.com points to 185.15.43.160. Every domain needs at least one A record to be accessible on the internet.

AAAA Record (IPv6 Address Record) Works exactly like the A record, but maps a domain to an IPv6 address instead. IPv6 addresses are longer and look like 2001:0db8:85a3:0000:0000:8a2e:0370:7334. As the internet transitions to IPv6, this record becomes increasingly important.

CNAME Record (Canonical Name Record) Points one domain name to another domain name instead of an IP address. It is commonly used for subdomains. For example, www.copahost.com can be set as a CNAME pointing to copahost.com, so both addresses lead to the same site.

MX Record (Mail Exchange Record) Defines which mail servers are responsible for receiving emails for your domain. Without a properly configured MX record, emails sent to your domain will not be delivered. Most domains have more than one MX record, with priority values that determine which server is tried first.

TXT Record (Text Record) Stores text-based information associated with a domain. It is widely used for domain ownership verification and email authentication protocols such as SPF, DKIM and DMARC — which help prevent spam and phishing attacks sent in your domain’s name.

NS Record (Name Server Record) Indicates which DNS servers are authoritative for your domain — in other words, which servers hold the official DNS records for it. When you register a domain and point it to a hosting provider, you are updating the NS records.

What is DNS Propagation?

DNS propagation is the time it takes for a DNS change to spread across all servers on the internet. When you update a DNS record, the change does not take effect instantly — it can take anywhere from a few hours to 48 hours for everyone worldwide to see the updated version.

We have a complete guide explaining how DNS propagation works and how to monitor it: What is DNS Propagation and how long does it take?

How to Check DNS Records

Checking DNS records is useful when troubleshooting email delivery issues, verifying domain configuration or confirming that a DNS change has propagated. There are several ways to do it:

Using an online tool

The easiest method is to use a web-based DNS lookup tool. Some reliable options are:

• MXToolbox — checks all record types with detailed output
• DNSChecker.org — shows propagation status from multiple locations worldwide
• whatsmydns.net — useful for checking if a DNS change has propagated globally

Simply enter your domain name, select the record type you want to check and run the lookup.

Using the command line

For more technical users, DNS records can be checked directly from the terminal:

On Linux or macOS:

dig copahost.com A
dig copahost.com MX
dig copahost.com TXTCode language: CSS (css)

On Windows (Command Prompt):

nslookup copahost.com
nslookup -type=MX copahost.com

These commands return the current DNS records directly from the authoritative name server, which is useful for verifying changes before they fully propagate.

What is DNS Cache?

DNS cache is a temporary storage of DNS lookup results kept by your browser, operating system or internet provider. Its purpose is to speed up browsing — instead of querying the DNS server every time you visit a website, your device reuses the result it already has stored locally.

Every cached record has a TTL (Time to Live) that determines how long it stays valid. Once the TTL expires, the cache is cleared and a fresh DNS lookup is performed.

Why does DNS cache matter? DNS cache is usually invisible and helpful. However, it can cause problems when DNS records change — for example, when migrating a website to a new server. Your device may keep loading the old IP address from cache even after the DNS has been updated globally.

How to clear DNS cache:

On Windows:

ipconfig /flushdns

On macOS:

sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

On Linux:

sudo systemd-resolve --flush-caches

On Google Chrome, you can also clear the browser DNS cache by visiting:

chrome://net-internals/#dnsCode language: JavaScript (javascript)

DNS Security: What is DNSSEC?

DNSSEC (Domain Name System Security Extensions) is a set of security protocols designed to protect the DNS system from attacks. It adds a layer of cryptographic verification to DNS responses, ensuring that the answer your browser receives actually comes from the legitimate authoritative DNS server — and has not been tampered with in transit.

Why is DNS security important? Without DNSSEC, DNS is vulnerable to a type of attack called DNS spoofing (or DNS cache poisoning), where a malicious actor injects fake DNS records into a resolver’s cache. This can redirect users from a legitimate website to a fraudulent one without them knowing — a technique commonly used in phishing attacks.

How does DNSSEC work? DNSSEC works by digitally signing DNS records using public-key cryptography. When a DNS resolver receives a response, it verifies the digital signature against a public key stored in the DNS. If the signature does not match, the response is rejected.

Should you enable DNSSEC for your domain? Yes, if your domain registrar and hosting provider support it. DNSSEC adds a meaningful layer of protection, especially for domains used for business email or e-commerce transactions where impersonation attacks are a real risk.

How to Change DNS Servers

Changing DNS servers can improve your internet speed, security or reliability. You may want to switch from your ISP’s default DNS to a faster public DNS server, or update your domain’s DNS to point to a new hosting provider.

Changing DNS servers for your domain (pointing to a new host)

This is done through your domain registrar’s control panel. The process updates your NS records to point to a different hosting provider:

1. Log in to your domain registrar account
2. Find your domain and access its DNS settings
3. Locate the Name Servers (NS) section
4. Replace the current name servers with the ones provided by your new hosting provider (e.g. ns1.copahost.com and ns2.copahost.com)
5. Save the changes and wait for DNS propagation (up to 48 hours)

Changing DNS servers on your computer or router

This changes which DNS server your device uses to resolve domain names — useful for improving speed or bypassing restrictions:

On Windows:

1. Go to Control Panel → Network and Internet → Network Connections
2. Right-click your connection and select Properties
3. Select Internet Protocol Version 4 (TCP/IPv4) and click Properties
4. Select Use the following DNS server addresses and enter your preferred DNS (e.g. Google’s 8.8.8.8 and 8.8.4.4)
5. Click OK to save

On macOS:

1. Go to System Settings → Network
2. Select your active connection and click Details
3. Go to the DNS tab
4. Click + to add a new DNS server address
5. Click OK and then Apply

Popular public DNS servers to consider:

Examples of domain name translating in a private DNS Server

Every time a user enters the domain name, DNS service translates it into the corresponding IP address. For a better understanding let’s explain.

For instance, a user enters the domain name “howstuffworks.com” in his/her browser. Soon after that, a request is made to the DNS server for resolving the domain name into an Internet Protocol (IP) address such as 70.42.251.42. This is how the process of DNS name resolution keeps on processing whenever it encounters a domain name.

What is a dynamic DNS server

Dynamic DNS (or DDNS) is a service that automatically updates your hostname with the current IP address of a server or a computer. This way, the dynamic DNS keeps on monitoring the IP addresses of your connection. Then, if the DDNS server detects any changes in your IP, then it automatically updates your DNS’s A (IPv4) or AAAA (IPv6) records.

This is useful for people who have an internet connection with a dynamic IP address (which changes every week, month or so..). By using a dynamic DNS server (or DDNS Server), you can have a permanent subdomain, always pointing to your current IP address. The dynamic DNS services stand for a system where the IP is often updated, where you use your subdomain whenever you need, and it will always point to your current IP… So, no matter if it changes!

There are some dynamic DNS services like No-ip.com and Dynu.com.