# Definition/Concept Guide

### API

API is short for application programming interface. An API is a way to access and send information to another server. For example, with the Discord API, you can access information from the specific Discord server, for example, messages, users, and server information. You can also send information with the API, for example sending a message in the chat or sending a user a private message.

### Environment Variables

Information that is stored that can be accessed through the code. This is particularly useful for information you do not want seen by anyone who reads the code. This is a type of [*variable*](#variable) that is hidden from plain sight, and is declared/retrieved in a different way than a normal variable. Reference [*creating environment variables*](https://sbdojo.gitbook.io/sushi-cards/2021-2022/session-1/day-1-setup/day-1-initialize-discord-bot#creating-environment-variables) for more information.

### Library

Libraries are a very helpful tool in coding in any language. It is code written by someone else that you can reference to do specific tasks. This will make the process of coding projects easier as you do not need to code everything but can rely on work from others. Some of these libraries come with the programming language, however, some may come from external authors.

### String

A string is a type of data. It is a bunch of characters (numbers, letters, symbols, spaces, etc.) combined together to form something like a sentence. It is usually created by putting the group of characters in quotes. For example `"Hello World!"` is a string.

### Variable

A variable is a way of storing data in your code. It can be changed throughout your code, unless it is defined as a constant variable (unneeded for this sushi card). It is created through a key-value system. This means you define a key, or a name that is referenced to access the value, the data that is stored. It is created by typing the following with *age* being the key and *15* being the value.

```python
age = 15
```