A Domain Registrar or Registration Service Provider is an entity that registers domains on behalf of clients. A Registrar will also manage a domain’s registration while it remains under their purview, which includes:
Every registered domain has an associated WHOIS record which contains information specific to that domain, including these important elements:
The DNS host is the entity responsible for hosting all of the DNS records for a domain. The DNS hosts (or servers) listed in a domain’s WHOIS record are the servers that house all of the DNS records for that domain. It is these DNS servers that inform the rest of the internet where e-mail for a domain should be routed to, where the website for a domain is located, etc.
A web hosting provider is a company that provides customers with access to a web server where they (the customer) can upload their website content so that it can be viewed by others on the web. Web hosting providers will also usually provide access to tools and applications that can aid with the website’s design and management, such as Content Management Systems, databases, and various programming languages.
A DNS record lets the rest of the internet know where to go to access specific services for a domain, such as its website, e-mail servers, etc. In some ways, a DNS record is analogous to an ‘Address Book’ or ‘Contact List’ entry on a phone. While an ‘Address Book’ or ‘Contact List’ entry on a phone associates a contact name with an e-mail address and/or phone number, a DNS record associates a domain or sub-domain with a corresponding host name or IP address.
To put it simply, a subdomain is a domain name with an additional host name (followed by a ‘.’) tacked onto the front. For example, ftp.execulink.ca, mail.execulink.ca, and subdomain.execulink.ca are all subdomains of the execulink.ca domain. Subdomains can also have more than one level. Thus, one.two.three.execulink.ca and web.hosting.execulink.ca are also subdomains of the execulink.ca domain.