Domains and DNS Explained for Non-Technical Website Owners

When something goes wrong with a website — it disappears, emails stop delivering, or new hosting does not resolve — the cause is almost always DNS. Understanding how domain names and DNS work gives you the knowledge to diagnose these problems yourself and make confident decisions when setting up or migrating websites.

What a Domain Name Is

A domain name is a human-readable address that maps to numerical IP addresses. IP addresses like 192.168.1.1 are how computers identify each other. Domain names exist because humans cannot memorise hundreds of numerical addresses. The Domain Name System (DNS) is the global directory — often called the internet's phonebook — that performs this translation.

How DNS Resolution Works

When you type a URL, your operating system asks a DNS resolver to look up the domain. The resolver queries authoritative name servers until it finds the record mapping the domain to an IP address. Your browser connects directly to that IP. This typically takes under 100 milliseconds and is completely invisible to the user.

The Four DNS Record Types You Need

An A record maps a domain to an IPv4 address — how your domain points to your server. A CNAME record maps one domain to another, used for www subdomains and hosting provider URLs. An MX record specifies which server handles email. A TXT record stores verification data for domain ownership, SPF, and other services. These four record types handle 95% of real-world DNS tasks.

DNS Propagation

DNS changes do not take effect instantly. Records have a TTL (Time To Live) value — how long resolvers cache them before re-checking. A TTL of 3600 means up to one hour for changes to propagate. Lower your TTL to 300 seconds 24–48 hours before a planned server migration so changes propagate in five minutes rather than 48 hours.