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# Environment Variable

## Introduction

* There are 2 types  - public & private
* There are 2 levels - static & dynamic

## Type

### Public

* Can be exposed on both client side and server side

### Private

* Can only be exposed on server side
* Suitable for variable that need to keep secret

## Level

### Static

* The variable only be appended during build time, if the variable is updated, the application is neede d to be rebuilt

### Dynamic

* The variable only be appended during run time, if the variable is updated, just restart the application is okay

## Reference

{% embed url="<https://learn.svelte.dev/tutorial/env-static-private>" %}