How the web works: browsers, servers, URLs, DNS, HTTP and hosting

Before going deeper into HTML, it helps to understand the journey a web page takes from a computer somewhere in the world to the screen in your hand. Knowing this makes you a better developer: you'll understand why sites are slow, why links break, what "hosting" and "domain" mean when a client asks, and where HTML fits.

The internet vs the web

People use the words interchangeably, but they're different:

The internet physically connects through undersea fibre-optic cables. Kenya is connected through several cables landing at Mombasa (such as TEAMS, SEACOM, EASSy, LION2 and PEACE), then fibre runs inland to data centres, mobile masts and homes. When a cable is damaged at sea, internet in East Africa can slow down for days, which shows how physical the internet really is.

Clients and servers

• A client is the device asking for something: your phone or laptop, using a browser (Chrome, Safari, Firefox, Edge, Opera Mini).
• A server is a computer that stores websites and sends pages when asked. It's usually in a data centre, running 24/7.

What a browser does

1. Takes the address you type or the link you tap.
2. Finds the server and requests the page.
3. Reads the HTML, requests the CSS, JavaScript, images and fonts it mentions.
4. Builds the page (the DOM), applies styles, runs scripts and draws it.
5. Handles your clicks, typing and scrolling.

Different browsers use different engines (Chromium/Blink for Chrome, Edge, Opera and Brave; WebKit for Safari; Gecko for Firefox). That's why testing in more than one browser matters.

URLs: the parts of a web address

https://shop.example.co.ke:443/products/laptops?brand=hp&page=2#reviews
└─┬─┘   └┬─┘ └─────┬────┘ └┬┘ └──────┬──────┘ └───────┬───────┘ └──┬──┘
scheme  sub   domain name  port    path          query string     fragment

Kenyan domain endings

These are managed by KENIC (Kenya Network Information Centre) and sold through accredited registrars. Global endings like .com, .org and .africa are also popular.

IP addresses and DNS

Computers find each other using IP addresses, numbers like 142.250.185.78 (IPv4) or longer ones like 2a00:1450:4001::200e (IPv6). Humans remember names better than numbers, so the Domain Name System (DNS) translates names into IP addresses.

The lookup, simplified:

1. You type example.co.ke.
2. Your device checks its memory (cache). If not found, it asks your internet provider's DNS resolver (Safaricom, Airtel, your Wi-Fi provider, or public ones like 1.1.1.1 / 8.8.8.8).
3. The resolver asks the root servers, then the .ke servers, then the domain's own nameservers, which hold its records.
4. The answer (an IP address) comes back and is cached for a while.
5. Your browser connects to that IP.

Common DNS records you'll meet when setting up sites:

HTTP and HTTPS

HTTP (HyperText Transfer Protocol) is the language browsers and servers use. The browser sends a request; the server sends a response.

A request (simplified):

GET /products/laptops HTTP/1.1
Host: shop.example.co.ke
User-Agent: Chrome on Android
Accept: text/html

A response:

HTTP/1.1 200 OK
Content-Type: text/html; charset=utf-8
Content-Length: 18240

<!DOCTYPE html><html>...

Methods

Status codes you must know

Groups: 2xx success, 3xx redirect, 4xx client mistake, 5xx server problem.

HTTPS: the S means secure

HTTPS encrypts the connection with TLS, so people on the same Wi-Fi, your internet provider or attackers can't read or change what's sent (passwords, M-Pesa numbers, messages). The padlock in the address bar shows HTTPS. Browsers label plain HTTP pages "Not secure", and Google prefers HTTPS sites. Certificates are free with Let's Encrypt and cPanel's AutoSSL, so there's no excuse for HTTP today.

Hosting and how a site goes live

To publish a website you need:

1. A domain name (e.g. mybakery.co.ke), rented yearly from a registrar. .co.ke domains typically cost around KSh 1,000–1,500 per year (prices vary by registrar).
2. Hosting: space on a server that's always online, rented monthly or yearly.
3. Files: your HTML, CSS, JavaScript and images, uploaded to the server (usually into a folder called public_html).
4. DNS pointing the domain to the hosting server.
5. An SSL certificate for HTTPS.

Kenyan hosting companies and international ones both serve Kenyan sites; servers closer to users (or a CDN) load faster.

CDNs

A Content Delivery Network (like Cloudflare) keeps copies of your files in data centres around the world, including Nairobi and Mombasa, so visitors download from a nearby location. It also protects against attacks.

Static vs dynamic websites

Either way, the browser always receives HTML. That's why HTML is the foundation.

The full journey, in one picture

You tap a link
   │
   ▼
Browser ── DNS lookup ──► "example.co.ke = 102.x.x.x"
   │
   ▼
Browser ── HTTPS request (GET /) ──► Web server (data centre)
                                         │ static: reads index.html
                                         │ dynamic: PHP + database build HTML
   ◄── HTTP response 200 + HTML ─────────┘
   │
   ├── requests CSS, JS, images, fonts (more requests)
   ▼
Browser builds the DOM, applies CSS, runs JS, paints the page

Common misunderstandings

Practice tasks

1. Break this URL into its parts: https://portal.school.ac.ke/results?year=2026&term=2#math.
2. Open DevTools → Network on a news site. How many requests does it make? What's the largest file?
3. Find a page that gives a 404 on a big website (type a made-up path). What does their 404 page offer?
4. Explain to a friend in three sentences the difference between a domain and hosting.
5. List the DNS records you'd need for a site at mybakery.co.ke with email at info@mybakery.co.ke.

Summary

• The internet is the network; the web is linked pages running on it.
• Browsers (clients) request pages from servers; the browser builds the page from HTML, CSS and JS.
• A URL has a scheme, (sub)domain, path, query string and fragment; .co.ke, .ac.ke, .go.ke etc. are managed by KENIC.
• DNS turns names into IP addresses; records include A, CNAME, MX and TXT.
• HTTP requests and responses carry pages; know status codes 200, 301, 404 and 500; always use HTTPS.
• Going live needs a domain, hosting, uploaded files, DNS and SSL. Static sites send the same files; dynamic sites build HTML on the server.