Port
ELI5 — The Vibe Check
A port is like an apartment number on a building. Your computer is the building (localhost), and multiple services live inside. Your web server is at apartment 3000, your database is at apartment 5432. The port tells traffic which service to knock on.
Real Talk
A port is a 16-bit number (0–65535) that identifies a specific process or service on a networked device. The OS uses ports to route incoming network traffic to the correct application. Well-known ports include 80 (HTTP), 443 (HTTPS), 5432 (PostgreSQL), and 6379 (Redis).
When You'll Hear This
"Make sure port 3000 isn't already in use." / "The firewall is blocking port 443 — that's why HTTPS fails."
Related Terms
Config
Config is the settings panel for your code.
Deploy
Deploying is taking your code from your computer and making it live on the internet for real users. Before: only you can see it.
Localhost
Localhost is your computer pretending to be a web server just for you.
Process
A process is a full running program with its own isolated chunk of memory.