Computers are connected together through a network of hardware and protocols.
Domain
Your domain name or website URL. You need to get one from a Domain Registrar.
Domain Registrar
A place like namecheap to buy domains.
Domain Name System (DNS)
DNS is responsible for looking up the IP address of a domain name.
Dynamic Host Configuration Protocol (DHCP)
Assign IP addresses automatically.
Name Server
Has the actual server IP addresses for a given domain name. A DNS lookup finds the domain registrar for the url and is directed to the specified nameserver to handle the response.
Subdomain
A url with an extra prefix and period. IE chat.andrewsclasses.com.
Ports
Application and I/O for an IP address.
HTTP traffic is sent and received by port 80.
Servers can "forward" their ports to other servers they connect to, allowing them to send and receive traffic a that address.
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