DNS stands for the Domain Name System, which is the system that looks up the name of a website, finds a corresponding number (similar to a phone number), then directs your request to the appropriate web server on the Internet.
Also See: Understanding Domain Names
Frequently Asked Questions
I don’t have my own site. Do I need to know a site’s DNS information?
No. DNS information is only important for website owners, name servers, and your computer. All you need to know about a website is it’s address, or its domain name, which is what you type into the address bar on your browser or where the link from your Google search takes you. When you direct your web browser to a specific domain, your computer contacts its name server and asks where that web address is stored. If its local name server doesn’t know, it will contact the next server up the chain, and so on until it finds where that site is hosted.
Why is the DNS information for a site different from the site’s web address?
All websites are hosted on web servers. When you go to a website, you are actually contacting the server that hosts that site and asking for the latest version of the webpage. Web servers host thousands of websites, and many servers are usually located in a single location, owned by a particularly webhosting company. The DNS information for a particular website is a lot like a street address for your home. It provides the name server with the location of the server that hosts that site. If more than one site is hosted on that server, the hosting server will point your computer to exactly the site you are looking for.
Does a site’s DNS information ever change?
Anytime a website owner switches web hosts, the site’s DNS information will change. This is because switching hosts also means switching the web server where the site is stored. After changing hosts, the site owner will update the DNS information with his or her domain registrar, which will then report the change to the Domain Name System. That way, the next time you try to visit the site, your browser can still find it, even though it is no longer in the same location as it was before. This is why domain names are so important. They provide consistency for Internet users, even though the actual locations of items on the Internet change all the time.