---
title: Payload Concepts
label: Concepts
order: 20
---

Payload is based around a small and intuitive set of concepts. Before starting to work with Payload, it's a good idea to familiarize yourself with the following:

### Config

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	The Payload config is where you configure everything that Payload does.
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By default, the Payload config lives in the root folder of your code and is named `payload.config.js`, but you can customize where you store it. The `config` is plain old JavaScript, meaning you can write full JavaScript functions and even full React components right into your config.

### Collections

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	A Collection represents a type of content that Payload will store and can contain many documents.
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Payload Collections are defined through Each Collection will map one-to-one with a MongoDB collection automatically based on fields that you define. You can have as many Collections as you need. It's often best practice to write your Collections in separate files,

### Globals

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	A Global is a "one-off" piece of content that is perfect for storing navigational structures, themes, top-level meta data, and more.
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You can define as many Collections as you need. On each Collection, you can specify the shape of your data through Fields.

### Fields

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	Fields are the building blocks of Payload. Collections and Globals both use Fields to define the shape of the data that they store.
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Payload comes with many different types of Fields that give you a ton of flexibility while designing your API. Each Field type has its own potential properties that allow you to customize how they work.