A quick overview of how the Web works, how the DNS works, and how our computers access and download websites.

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Domains & DNS

Domains vs. IPs

  • We use domains to access websites — but computers need IP addresses
  • IP addresses are confusing for humans
127.0.0.1
2001:0db8:85a3:0000:0000:8a2e:0370:7334

DNS

(Domain Name System)

Maps Domains ⬌ IPs

DNS records

Each registered domain has a bunch of information attached to it—here’s some important entries:

  • NS — The authoritative DNS information server
  • A — The domain to IP mapping for the host
  • MX — The email server location
  • CNAME — A subdomain or alias for the A record

Leasing domains

  • Leasing a domain registers it in the DNS
  • And points the domain to an IP address — the host
  • Also points to where email is sent and received

Don’t buy everything in one place

Don’t buy your hosting, email & domains all from the same place!

  • It may be convenient to start but will get really annoying
  • Difficulty switching — if you want to change host, well, now you likely have to change all services
  • Security — if one is compromised they all are

CloudFlare

  • Becomes our DNS server
  • Provides performance boost
  • Provides great security
  • Provides better DNS solutions for hosting on GitHub

Videos & tutorials

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A quick overview of how the Web works, how the DNS works, and how our computers access and download websites.