what is DNS?

The DNS plays a very critical role in working of the internet. Without it, it is likely no internet ever-present.
DNS can be addressed as an address book which provides address for websites.It is the component responsible for translating the email and websites into an IP understandable for the computer to communicate with each other.This helps the user to easily remember the websites as name which is easy to remember that address.
The most commonly used DNS address is 8.8.8.8 and 8.8.4.4 (Google Public DNS).

Do I need DNS service?

For accessing the internet a DNS is must, Most people are usually using the DNS services provided by their providers, The DNS services provided by user internet service provider typically slower and vulnerable than Public DNS, The ISP DNS will not provide any website browsing securities.

What is OpenDNS, Google DNS and others in this same field?

OpenDNS is a San Francisco based tech company that provides various solutions to Web securities and navigation problems
for businesses of all sizes.The OpenDNS(208.67.222.222, 208.67.220.220) helps to increase the navigating websites speed and provide security against phishing
and malware sites.

Google DNS is a public DNS maintained by Google. Google DNS also provides Good Website Loading Speeds and Provide security sites.

There are many others who provides public DNS.

Few of them are

http://www.freenom.world/en/index.html?lang=en (80.80.80.80, 80.80.81.81)

https://dns.norton.com/

Why Should we use Public DNS

Public DNS such as OpenDNS and Google DNS provides better DNS services than any other DNS services.OpenDNS and Google DNS helps you to quickly reach to your websites and helps you to never experience outages again.
Good Public DNS is a most efficient way to prevent phishing sites, virus and malware infections.
How is OpenDNS, Google DNS faster than others?
OpenDNS helps provide better and faster speed with the help of global network servers which automatically send your DNS
requests to closet OpenDNS datacenter, This helps to significantly increase the accessing speed because your present DNS is likely hosted in a location far from your location.