Computers communicate with each other over networks and the World Wide Web (WWW) using IP addresses (e.g. 192.168.2.1). Each device on a network, or the WWW, has a unique IP address. Websites are stored on web servers that have a unique IP address. If you were to type the IP address of a web server into your browser’s address bar, together with a path to the folder that the website is stored in, the web site will be displayed in your browser.
Unfortunately, IP addresses, and paths to a web site’s folder, are hard to remember. So Uniform Resource Locators (URLs, commonly referred to as web addresses) were invented. Instead of typing in the IP address and path to a website, you can just use a website’s much more memorable URL (e.g. g7lfc.radio).
After submitting a URL to your browser it will perform a DNS lookup. It contacts a Domain Name System (DNS) server and asks it to lookup the IP address associated with the URL. The browser then sends a request to the web server on that IP address.
Think of a the DNS as a telephone book. So long as you know the name of the person you are looking for, you can find their address using the telephone book. In the land of the WWW, the DNS stores the name (URL) of a web site and its associated IP address. It turns hard to remember IP addresses into easy to remember URLs.