How a website actually works

When you open a website, four things are involved. The clearest way to see them is a restaurant.

Walking through one click

You click "My Orders" on a shopping site.

1. 1Frontend (the page in your browser) notices the click.
2. 2It sends a request to the API: "orders for user 4471, please."
3. 3The backend on a server receives it, checks you're really logged in, and asks the database.
4. 4The database returns 12 rows of order data.
5. 5The backend formats them and sends them back.
6. 6The frontend turns that data into the list you see.

All six steps in about 200 milliseconds.

The words you'll hear in meetings

The three languages of the frontend

If you ever peek at a web page's code, you'll meet these:

• HTML — the structure. "This is a heading, this is a paragraph, this is a button." Like the skeleton.
• CSS — the appearance. "Headings are blue and 24 pixels." Like the clothes.
• JavaScript — the behaviour. "When this button is clicked, show that box." Like the muscles.

Why does a website ever go down?

Now you can reason about it properly:

• Server is overloaded — too many people at once. The kitchen has too many orders.
• Database is slow — one query is taking forever. The store room is disorganised.
• A deploy went wrong — new code was released and broke something.
• Your internet — everyone else can see the site fine.

Being able to ask "is it the frontend or the backend?" in a meeting will get you taken seriously immediately — because it's the question that halves the problem.