HTTP

Sentry is an error-tracking and performance-monitoring platform to help developers diagnose and fix issues in their code.

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

How the apps you access in your browser actually work.

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.