Domain names are a fundamental part of the internet. They are the human-friendly web addresses we use every day to access websites, like "google.com", "wikipedia.org", or "amazon.com". But have you ever stopped to think about how domain names actually work behind the scenes?
In this comprehensive guide, we‘ll dive deep into the world of domain names. We‘ll cover the technical details of what makes up a domain name, how the domain name system resolves them into IP addresses, the history and evolution of domains, and much more. Whether you‘re looking to register a domain for a new website or just curious about the inner workings of the internet, this guide will provide you with a thorough understanding of domain name basics.
Anatomy of a Domain Name
Before we get into how domain names work, let‘s first break down the components that make up a domain name. A fully qualified domain name (FQDN) consists of several parts:
- Top-Level Domain (TLD): The last part of the domain name, like .com, .org, .net, etc. Indicates the purpose or location of the website.
- Second-Level Domain (SLD): The main part of the domain name, like "google" or "wikipedia". Identifies the specific website.
- Subdomain (optional): A division that comes before the SLD, like "mail" or "support". Used to organize different sections of a website.
There are also some additional optional parts that can be included:
- Additional subdomains (e.g. world.news.bbc.com)
- Port number (e.g. :8080)
- Username/password (e.g. user:[email protected])
However, most domain names used for websites consist simply of a TLD and SLD, sometimes with the "www" subdomain preceding it.
Syntax rules for domain names include:
- Maximum of 255 characters
- Each label (part separated by dots) limited to 63 characters
- Can only use a-z, 0-9, and hyphen (-)
- Cannot start or end with hyphen
- Case insensitive
Types of Top-Level Domains
As of 2021, there are over 1,500 different top-level domains available for registration. However, they generally fall into one of three categories:
- Generic TLDs (gTLDs): The most common type of TLDs, these include the original options like .com, .org, and .net, as well as newer options like .biz, .info, .shop, and hundreds of others. As of 2021, the most popular gTLDs by number of registrations are:
| Rank | TLD | Number of Domains |
|---|---|---|
| 1 | .com | 151.8 million |
| 2 | .tk | 27.7 million |
| 3 | .cn | 24.7 million |
| 4 | .de | 16.6 million |
| 5 | .net | 13.4 million |
Sources: Verisign Domain Name Industry Brief, DomainTools
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Country Code TLDs (ccTLDs): Two-letter TLDs based on country codes, like .us (USA), .ca (Canada), .jp (Japan), etc. Used to show the country a website is based in or targeting. ccTLDs make up a significant share of domain registrations, with the .tk ccTLD (Tokelau) actually being the second most registered TLD due to its free registration model. Other popular ccTLDs include China (.cn) and Germany (.de).
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Sponsored TLDs (sTLDs): TLDs with a sponsor organization that sets policies for its usage. These include .edu (post-secondary institutions), .gov (U.S. government), .mil (U.S. military), and more.
In recent years, ICANN (the organization that oversees the domain name system) has greatly expanded the number of TLDs, with the goal of enhancing consumer choice and competition. Some of the newer TLD options proving popular include:
- .io: Associated with tech/software startups, popular for its input/output meaning
- .co: Originally the ccTLD for Colombia, now used more generally as a shorter .com alternative
- .ai: Associated with artificial intelligence and rising in popularity with tech companies
- .app: One of the most popular new gTLDs, used for mobile/web apps
How the Domain Name System Works
Now that we understand the structure of domain names, let‘s look at how they actually work to take us to websites. This is where the domain name system (DNS) comes into play.
The DNS is a distributed database that maps domain names to IP addresses. Its primary purpose is to make the internet more human-friendly by allowing us to use memorable domain names instead of memorizing long strings of numbers. When you enter a URL into your browser, the DNS works behind the scenes to resolve the domain name into the IP address needed to access the website.
The DNS resolution process involves several steps:
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When you enter a URL, your device first checks its local DNS cache to see if it already knows the IP address. If not, it sends a query to the recursive resolver, typically managed by your ISP.
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The recursive resolver also checks its cache. If no record is found, it starts the recursive search process by querying the root nameservers.
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The root servers respond with the location of the TLD nameservers for the domain (e.g. .com, .net, etc.)
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The recursive resolver then queries the appropriate TLD nameserver, which responds with the location of the SLD nameserver (e.g. the "google" of "google.com").
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The recursive resolver then queries the SLD nameserver, which holds the actual IP address record for the domain.
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The IP address is returned to the recursive resolver, which passes it back to your device. It also caches the record for faster lookups next time.
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Your browser contacts the IP address and loads the website.
All of this happens in milliseconds without the user needing to be aware of the complex lookup process. The distributed nature of the DNS, with its hierarchy of caching resolvers, helps to manage the billions of requests and keeps things running smoothly.
Choosing a Good Domain Name
With the abundance of TLDs now available, choosing a good domain name for a new website can seem like a daunting task. While there‘s no one-size-fits-all approach, here are some general tips to keep in mind:
- Keep it short: Aim for under 15 characters. The shorter and more concise, the easier it will be to remember and less prone to typos.
- Make it brandable: Your domain is a key part of your online identity, so make sure it aligns with your brand. Avoid generic keywords and focus on being unique and memorable. That said, it‘s okay to use keywords if they are part of your brand name or help clarify what your site is about.
- Avoid numbers and hyphens: They make your domain harder to remember and communicate verbally. If you need to differentiate, consider using a different TLD instead of words/numbers (e.g. getcarinsurance.com vs. get-car-insurance.com or getcarinsurance1.com).
- Check for trademark conflicts: To avoid legal issues down the road, do a trademark search to make sure your domain doesn‘t infringe on any existing marks.
- Consider how it looks and sounds: Think about how your domain looks as a URL and sounds when said aloud. Watch out for unintended words or meanings when parts are put together (e.g. therapistfinder.com).
- Opt for the .com TLD if possible: It‘s still the most recognized and trusted TLD, so if the .com version of your domain is available, it‘s usually worth securing. However, other memorable options like .co, .us, .biz, .io, etc. can also work.
If your ideal domain is already taken, you can try some variations like:
- Adding qualifying words (e.g. verb + brand name, or brand name + location)
- Using a different extension
- Modifying the spelling (while still keeping it recognizable)
Ultimately, while a good domain name is important, don‘t get too hung up on finding the "perfect" domain. With a strong brand and quality content, you can make almost any domain work.
Domain Name Registration
Once you‘ve picked out an available domain, it‘s time to register it so you can start using it for your website. The registration process is handled by domain registrars, which are accredited by ICANN. Some of the most popular domain registrars include:
- GoDaddy
- Namecheap
- Google Domains
- Bluehost
- HostGator
- Dreamhost
To register a domain, you‘ll need to:
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Choose a registrar and check the availability of your desired domain.
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Select your desired domain term (1-10 years). Registrars often offer discounts for longer registration periods.
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Provide your contact information (name, address, phone, email) for the domain‘s WHOIS record.
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Select add-on services if desired, like domain privacy or automatic renewals.
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Complete the checkout process to pay the registration fee.
Upon successful registration, you‘ll receive a verification email with the next steps to start using your domain. Note that new domains may take up to 24-48 hours to fully propagate worldwide.
It‘s critical to provide accurate contact information and keep it up-to-date, as this is how you‘ll recover your domain if you lose access to your account. However, the public WHOIS directory allows anyone to look up a domain‘s registration details, so you may want to opt for domain privacy to hide your personal info and cut down on spam.
Remember that you don‘t own your domain outright, but are rather leasing it for your selected term. Be sure to renew your registration before it expires to maintain control of the domain. Most registrars offer auto-renewal to help prevent unintended expirations.
The Domain Aftermarket
Given the lucrative nature of domain names, it‘s no surprise that there‘s a booming aftermarket for buying and selling valuable domains. If the perfect domain for your project is already registered, you may be able to acquire it from the current owner – for the right price.
Short, generic domains are highly prized for their brandability and memorability. Especially rare one-word .com domains have sold for millions – see cars.com ($872 million), lasvegas.com ($90 million), and carinsurance.com ($49.7 million). Even longer domains can carry huge valuations if they are based on a popular search term.
If you‘re interested in acquiring an already registered domain, you can check its availability using a WHOIS lookup tool like ICANN‘s or DomainTools. Many registrars also offer these tools. If the domain is marked as available, that means the current owner is likely willing to sell.
You can try contacting the owner directly via their WHOIS contact email. There are also a number of domain marketplaces, like Sedo, GoDaddy Auctions, and Flippa, where you can search for domains listed for sale or let the owner know you‘re interested. Keep in mind that many transactions happen privately, so a domain not being overtly listed for sale doesn‘t necessarily mean it‘s unavailable.
To protect their investment, many companies proactively register variations of their brand name, common misspellings, and other TLDs beyond just the .com. This helps guard against cybersquatting, typosquatting, and other bad faith registrations looking to capitalize on their brand.
The Future of Domains
As the internet continues to evolve, so does the domain industry. Emerging technologies and changes in online behavior will undoubtedly impact how we use and think about domain names going forward.
One development to watch is the rise of alternative naming systems that operate outside of the traditional DNS. For example, blockchain-based projects like Unstoppable Domains and Handshake are using crypto technology to provide more secure, decentralized options for domain registration and website access. These systems aim to give users more control and privacy, and also open up new possibilities like linking domains directly to crypto wallets.
The growth in mobile web usage may also drive demand for shorter TLDs that are easier to type on small screens. With mobile devices accounting for over 54% of worldwide web traffic (Statista), businesses may increasingly opt for concise, mobile-friendly domains to improve user experience.
Voice-based interfaces and virtual assistants may diminish the importance of memorable domain names, as users turn to verbal queries to find information vs. typing in URLs. However, domains will remain crucial for businesses to control their online presence vs. relying on third-party platforms.
As the internet becomes more globalized, ccTLDs and IDNs (internationalized domain names that support characters beyond the Latin alphabet) will likely continue to grow in significance. Savvy businesses will secure localized versions of their domains to better serve different geographic markets.
Looking ahead, the domain aftermarket shows no signs of cooling. A 2019 study valued the domain aftermarket at $1.4 billion, with a 2024 projection of $2.1 billion (Global Market Insights). As more businesses move online and the supply of memorable domains continues to decrease, acquisition costs will likely keep rising for premium domains. Consider that in 1994, mcdonalds.com sold for just $3,500, while in 2019, voice.com went for $30 million!
All in all, while domains will undoubtedly evolve with the internet, their fundamental value and necessity as online identifiers will persist. Understanding how they work and following best practices for domain selection and management will remain essential for businesses and individuals looking to stake their claim on the web.
