Step 1 — How the internet works

When you type codingstairs.duckdns.org into your browser, four steps happen automatically.

1. DNS lookup — domain name → IP address
2. HTTP request — your browser asks port 443 of that IP for the page (HTTPS = encrypted HTTP)
3. Response — the server returns HTML/CSS/JS plus data
4. Render — the browser turns that into pixels on screen

nslookup codingstairs.duckdns.org
# → prints the IP address

Four words you'll use forever

• URL — a single-line address like https://codingstairs.duckdns.org/edu/...
• HTTP/HTTPS — the request/response protocol; HTTPS adds encryption
• DNS — a distributed phonebook of names → IPs
• Port — a numbered "window" into an IP (HTTP=80, HTTPS=443, dev server=3000…)

Try it

Open DevTools (F12) → Network tab → reload the page. Every request and response shows up. Click any one to see headers, body, and timing. Keeping this tab open habitually solves half of all bugs.

Going deeper

• HTTP & REST
• URL anatomy
• Browser DevTools

Next

Step 2 turns those HTML responses into pages with meaning.