Every website on the internet has a unique IP address assigned to it, made up of a series of numbers. These numbers tell the domain name system (DNS) to locate the corresponding website. As we are humans and not computers, IP addresses are difficult to remember and so words are used instead. These words are known as the domain or URL. The DNS looks at the domain name and translates it into an IP address.
^ Mockapetris, P.V. (November 1987). "Domain names - concepts and facilities" (HTML). IETF Documents. IETF. doi:10.17487/RFC1034. Retrieved 24 July 2017. Relative names are either taken relative to a well known origin, or to a list of domains used as a search list. Relative names appear mostly at the user interface, where their interpretation varies from implementation to implementation, and in master files, where they are relative to a single origin domain name. The most common interpretation uses the root "." as either the single origin or as one of the members of the search list, so a multi-label relative name is often one where the trailing dot has been omitted to save typing.
Contact the owner. Before so much as hinting at a price, simply email to ask whether or not the domain is for sale. If you are known or can clearly be linked to a thriving business, create a generic alternate email address through which to contact them, as your success might be leveraged against you. Be aware, however, that an informal-sounding email address is more likely to be regarded as spam or junk mail.
It's good to decide early on if you want to have a brand domain or a keyword domain. The benefit of a brand domain is that your domain will most likely be considered as trustworthy, and immediately shows visitors that it's linked to your business or personal blog. A keyword domain, on the other hand, has the advantage that it will be better optimized for search engines, and therefore will get higher search results. In recent years, however, the drastic improvement in search results thanks to a keyword domain has begun to decrease.
Think of the name you want to register. The answer is typically your company or website name. It is best to keep your domain name short and easy to understand. Say it out loud, and make sure it sounds great. Next, search to see if it is available. If the name you desire is taken with the .com top-level domain, there are hundreds of others available. Finally, add the top choices to your cart and complete the domain registration.
Make sure you always retain control of your domain name. There are hundreds of businesses hosting their websites with a web host they’re not happy with. Poor service, surprise invoices, unreliable uptime and email issues are just some of the common issues customers are facing today. What most of them want to do is vote with their feet and walk out the door and find another web hosting provider. They don’t go through with it, however, because moving all their domains to another host is a complete admin headache. Choose wisely from the get-go so you don’t become one of these customers.
You should also avoid words that have more than one spelling if your visitors are likely to be confused and mistype the name. Alternately, you can buy both versions of the name and direct visitors from the one you like less to the preferred name. While you do want a short name (see below), don’t go for something so cryptic that people have a hard time remembering it. Word of mouth is a powerful marketing tool and you want to make it easy for people to tell their friends about your site.