What is an environment variable?

An environment variable is a setting kept outside the code, usually because it is a secret: a password, a key, a database connection. Apps read them at the moment they run. The reason they exist is so secrets are never written into files that get shared or published.

This is the single most common way people accidentally publish something they should not have. A key pasted into a file, the file pushed somewhere public, and within hours automated scanners have found it. It happens to experienced developers regularly.

Ura keeps these values out of everything that travels. They are not included in the encrypted copy of your projects that follows you between computers, because a secret that is backed up everywhere is not really a secret.