How Websites and Servers Work
Understand the request-response cycle and the physical components that make up a server.
By the end of this lesson, you will be able to:
- Explain the "Request-Response" cycle of a website.
- Identify the core physical components of a server (CPU, RAM, Storage).
- Define basic IT terminology like IP Addresses and DNS.
The Core Idea
Every time you visit a website, you are asking a computer somewhere else in the world to send you some data. That computer is called a Server, and your computer is called the Client.
1. How a Website Loads
Think of it like ordering at a restaurant:
- Request: You (the Client) ask for a page (the Menu).
- DNS: Since computers use numbers (IP addresses) and humans use names (google.com), the Domain Name System (DNS) acts like a phonebook to find the right server.
- Processing: The Server receives the request and prepares the data.
- Response: The Server sends the data back to your browser to display.
What is a Server Composed of?
A server is just a powerful computer. Like your laptop, it has four main parts:
CPU (Compute) — The processing power. Executes every instruction, calculation, and decision the server makes.
RAM (Memory) — The short-term workspace. Holds data that is actively being used, like a kitchen counter during cooking. Fast, but cleared when power is off.
Storage (Disk) — The long-term data layer. Persists files and databases even when the server is off, like a pantry or fridge.
Network — The connectivity layer. Moves data in and out of the server, like a delivery driver shuttling packages between locations.
In the cloud, we call these Resources. When you "scale up" a server, you are usually adding more of these.
Essential IT Terminology
To talk about the cloud, you need to know these three terms:
- IP Address: The unique number (e.g.,
192.168.1.1) that identifies every device on the internet. - Protocol: A set of rules for how data is sent (e.g., HTTP for websites).
- Data Center: A giant building filled with thousands of these physical servers.
Micro-activity: Hardware Simulator
That AWS server has 96× more RAM
That AWS server has 48× more cores
Your machine
2 GB RAM · 2 cores
AWS r6i.48xlarge
192 GB RAM · 96 cores
What this spec can handle
Personal website
A static blog or portfolio site with light traffic.
Small web app
A simple web app serving ~100 concurrent users.
Medium web app
A production app handling ~1,000 concurrent users.
Database server
A relational DB like PostgreSQL under moderate load.
Video transcoding
Processing and re-encoding video uploads in real time.
ML model training
Training a mid-size machine learning model.
Large-scale analytics
Running analytics queries across millions of rows.
Enterprise data warehouse
Petabyte-scale data warehouse used by a Fortune 500.
Drag the sliders up to unlock more workloads
Think about it
Someone's office building vs. cloud data centers
Think: Black Friday surges, viral moments, breaking news
Think about cost, staffing, physical space, and hardware failures
Your answers are saved automatically.
Summary
Websites work through a simple cycle of requests and responses. Behind every "cloud" service is a physical server composed of CPU, RAM, and Storage, connected to a global network.