Examine the functions executed by the Domain Name System (DNS) and support your discussion with a practical example to illustrate its role and significance.

The Domain Name System (DNS) is a crucial component of the internet that serves as the internet's phone book. It is responsible for translating human-friendly website names such as "www.google.com" into IP addresses that computers use to identify each other on the network.

Here are the main functions executed by the DNS:

1. Domain Name Resolution: This is the primary function of DNS. It translates domain names into IP addresses. When you type a URL into your browser, the DNS looks up the domain name and finds the corresponding IP address.

2. Domain Name Registration: DNS also manages the registration of domain names. When a domain name is registered, it is added to a large domain name register, and information about the website - including the IP address - is stored on a DNS server.

3. Load Balancing: DNS can distribute requests for a particular domain to different IP addresses to balance the load of incoming traffic. This is particularly useful for large, high-traffic websites.

4. Redundancy and Fault Tolerance: DNS provides a level of redundancy and fault tolerance by allowing multiple DNS servers to store the same domain information. If one server fails, another can take over.

Now, let's illustrate this with a practical example:

Suppose you want to visit the website "www.example.com". You type this URL into your web browser. Your computer doesn't know the IP address for this site, so it sends a request to the DNS. The DNS server searches its database and finds the IP address associated with "www.example.com". It then returns this IP address to your computer. Your computer then uses this IP address to connect to the server hosting "www.example.com" and retrieve the website content.

Without DNS, you would have to remember and enter the IP address directly, which is not practical or user-friendly. Therefore, DNS plays a significant role in the functionality and usability of the internet.