# The Address Book of the Web: Understanding DNS Records How does a browser know where a website lives? If you type `himanshubalani.com` into your browser and press Enter, your computer faces an immediate problem. It has no idea what or who "himanshubalani" is. Computers don’t understand words; they understand numbers. Specifically, they route traffic using IP addresses like `184.193.118.123`. To bridge this gap, we use the **Domain Name System (DNS)**. You will often hear DNS described as the "phonebook of the internet." You look up a human-friendly name (a domain), and the phonebook gives you the machine-friendly number (the IP address). Learn more about here - [**How the Internet Routes Your Requests with DNS**](https://blog.himanshubalani.com/how-the-internet-routes-your-requests-with-dns) But a domain name isn't just a single destination. Modern domains act more like an entire office building. You might want your main website hosted on GitHub, your blog hosted on Hashnode, a side project hosted on Vercel, and your emails routed to Gmail. To make all of this work simultaneously, the DNS "phonebook" doesn't just hold one number. It holds different **types of records**. Let’s open up the actual DNS settings for my personal domain, `himanshubalani.com`, and use it to understand what each DNS record does and why it exists. * * * ### The NS Record: The Receptionist **NS** stands for **Name Server**. Before anyone can read your DNS records, they need to know *who is storing them*. When you buy a domain from a registrar (like Porkbun, Namecheap, or GoDaddy), an NS record is created. It essentially says: "If you want to know anything about `himanshubalani.com`, go ask Porkbun's servers. They have the master list." **What problem it solves:** It delegates authority. It tells the global internet exactly which server holds your specific configuration. * * * ### The A Record: The Street Address **A** stands for **Address**. This is the most fundamental DNS record. It points a domain name directly to an **IPv4 address** (the classic format like `192.168.1.1`). When you visit my main portfolio, my DNS contains four A records: ```text Type Host Answer A himanshubalani.com 185.149.118.161 A himanshubalani.com 185.149.119.161 A himanshubalani.com 185.149.111.161 A himanshubalani.com 185.149.112.161 ``` *Why four?* My main site is hosted on GitHub Pages. GitHub gives me four different IP addresses for redundancy. If server `108.149` goes down, the browser simply tries `119.161`. **What problem it solves:** It tells the browser the exact server machine to connect to. * * * ### The AAAA Record: The Modern Street Address **AAAA** (Quad-A) works exactly like an A record, but for **IPv6 addresses**. We are running out of traditional IPv4 addresses, so the internet created IPv6 (which looks like `2001:0db8:85a3:0000:0000:8a2e:0370:7334`). AAAA records exist simply to map a domain to these newer, longer addresses. * * * ### The CNAME Record: The Alias **CNAME** stands for **Canonical Name**. Instead of pointing to an IP address (a number), a CNAME points a domain to *another domain name*. Think of it as an alias or a forwarder. I use subdomains to organize my projects. I don't want to manage the underlying IP addresses for all of these platforms, because if they change their server IPs, my websites would break. Instead, I use CNAMEs: ```text Type Host Answer CNAME blog.himanshubalani.com hashnode.network CNAME album.himanshubalani.com 238787b997276420.vercel-dns-017.com. ``` When you type `blog.himanshubalani.com`, DNS looks at the CNAME and says: *"I don't have the IP address, but* `hashnode.network` *does. Go ask them."* The browser seamlessly follows the path to Hashnode's servers. > **A vs CNAME (The beginner confusion):** > > * An **A Record** must point to an **IP address** ( `185.149.118.161` ) . > > * A **CNAME Record** must point to a **Domain Name** (`hashnode.network`). > > * You cannot put an IP address inside a CNAME. > * * * ### The MX Record: The Mailroom **MX** stands for **Mail Exchange**. Web traffic (HTTP) and email traffic (SMTP) are two totally separate things. When you send an email to `hello@himanshubalani.com`, the sending email server doesn't care about my A records. It only looks for MX records. ```text Type Host Answer Priority MX himanshubalani.com fwd1.porkbun.com 10 MX himanshubalani.com fwd2.porkbun.com 20 ``` These records tell the world: *"If you have an email for this domain, hand it over to Porkbun's mail servers."* (The `Priority` number just tells it which server to try first). > **NS vs MX (The beginner confusion):** > > * **NS** tells the internet who manages your *DNS settings*. > > * **MX** tells the internet where to deliver your *emails*. > * * * ### The TXT Record: The ID Badge and Sticky Notes **TXT** stands for **Text**. TXT records don't route traffic. They are simply sticky notes attached to your domain where you can write arbitrary text. Today, they are primarily used for **verification** and **security**. When I set up Google Search Console, Google needed to know I actually owned the domain before giving me analytics. They asked me to add a TXT record with a secret code: ```text Type Host Answer TXT himanshubalani.com google-site-verification=oc6RfofjIQEq-Lk... TXT pl.himanshubalani.com peerlist-domain-verification=uh3a6a0z... ``` Google checks my DNS, sees the code, and says, *"Okay, you definitely own this bro. my bad"* TXT records are also vital for email security. I have a TXT record starting with `v=spf1`. This is a security policy that tells other email providers (like Gmail) exactly which servers are legally allowed to send emails on my behalf, preventing spammers from spoofing my address. * * * ### Pulling It All Together When you look at a DNS dashboard for the first time, it looks like a random spreadsheet. But once you understand the pieces, it reveals a beautifully modular system. With one single $10 domain (`himanshubalani.com`), I am simultaneously: 1. Hosting my portfolio on GitHub (**A Records**) 2. Running a blog on Hashnode (**CNAME**) 3. Receiving custom emails through Porkbun (**MX**) 4. Proving my identity to Google and Peerlist for custom domain integration and SEO optimzation (**TXT**) DNS is not magic. It is just a public spreadsheet. Your browser asks a question, the spreadsheet provides the answer, and the internet connects the dots.