Operating System

Every operating system is built off of a kernel, which is the core of the OS, doing most of the hardware management.

The basics of how apps are built by their component parts.

Heroku was and is one of the first cloud platforms as a service (PaaS).

Computers have digital ports – literally, like for a boat – for other computers to connect to over a network. Ports map to specific things that an operating system might be doing, and there are some standard ones: port 22 is where you log into via SSH, port 80 is HTTP, port 443 is HTTPS (HTTP, but secure), port 53 is DNS, and so on and so forth.