Infrastructure Basics: Domain, DNS, Hosting, SSL and Server

• Domain: the human-readable address of a website (e.g. zee.design), like a street and house number in the real world.
• DNS (Domain Name System): the "phone book" of the internet that translates a domain name into the server's numeric IP address.
• Web hosting / server: a computer in the cloud that runs around the clock and serves your website's files to visitors.
• SSL / HTTPS: a security certificate that encrypts traffic (the padlock icon). Without it, browsers mark the site as "Not Secure".
• IP address: the unique numeric identifier of a server on the internet (e.g. 76.76.21.21).

Think of a website as your company's physical office:

• The domain is your street address and the sign on the building (e.g. "123 Main Street" = "mycompany.com").
• DNS is the GPS that tells the driver (the browser) exactly which coordinates (IP address) to go to.
• Hosting / the server is the building itself, with the rooms that hold all your furniture and products (code files, images, text).
• The SSL certificate is the security guard at the door who makes sure nobody can listen in on the conversation between you and your guest.

A common point of confusion for beginners:

• Apex (root) domain: the bare name with nothing in front, e.g. zee.design.
• Subdomain: a prefix in front of the domain used for a separate service, e.g. app.zee.design (an app), blog.zee.design or shop.zee.design.
• The "www" prefix is historically just another subdomain, usually pointed at the same server as the apex.

1. Find the IP address behind a domain (ping)

   ping zee.design

   Prints the IP address of the server that is currently answering requests.

With platforms like Vercel and Cloudflare, you no longer need to pay for an SSL certificate every year. They issue certificates for free and renew them automatically.