Plain-English explanations of every term used elsewhere in this wiki.
ACL (Access Control List) A named list of who's allowed to do something — either a list of allowed networks/IP addresses, or a list of login usernames and passwords. See Protecting a Site.
Bind / bind address Which of the server's own network addresses a website or rule should "listen" on for incoming visitors. Most people leave this on "All interfaces," meaning "answer on any address this server has." IPv4 and IPv6 are the two different addressing systems the internet uses side by side today — most servers have both, and rust-proxy can listen on either or both at once.
Certificate / HTTPS certificate The thing that puts the padlock icon in a visitor's browser. Proves a website is really who it says it is and encrypts the connection. See HTTPS Certificates, Explained.
DNS (Domain Name System)
The internet's phone book — it's what translates a domain name like example.com into the actual server address it should reach. Managed through your domain registrar or DNS provider, not through rust-proxy.
Domain
A website address, like example.com or app.example.com.
Firewall A guard that decides which network connections are allowed to reach the server at all, and which are blocked outright. rust-proxy's firewall is locked down by default (everything blocked) except for what you explicitly open — see Opening Other Ports and Protecting a Site.
Host rust-proxy's term for one website entry — a domain name plus where it actually points. See Adding a Website.
HTTPS The secure, encrypted version of the web (the padlock icon). Nearly all modern websites use it.
Port A numbered "door" on a server that a specific kind of traffic uses — 443 for secure websites, 80 for regular (insecure) websites, and different numbers for other services. See Opening Other Ports.
Port rule An entry in the Firewall / port rules tab that opens a specific port for a non-website service. See Opening Other Ports.
Redirect A host that, instead of showing a website, automatically sends visitors somewhere else. See Adding a Website.
Upstream
Where a host's real website actually lives — usually an address and port on this same server, like 127.0.0.1:8000.
Wildcard certificate
A single HTTPS certificate that covers an entire family of subdomains at once (e.g. anything ending in .example.com), instead of needing one certificate per subdomain. Requires the DNS-check method described in HTTPS Certificates, Explained.