> For the complete documentation index, see [llms.txt](https://nkrishang.gitbook.io/pack-protocol/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://nkrishang.gitbook.io/pack-protocol/how-pack-protocol-works/overview.md).

# Overview

$PACK Protocol is an open market for packs filled with exclusive rewards. Simply put, this means:

* Anyone can create and sell packs filled with rewards.
* Anyone can buy, and claim or resell packs and rewards.

The concept of $PACK Protocol is simple - it can be seen in old school products unrelated to blockchains, like [Pokemon card packs](https://www.pokemoncenter.com/category/booster-packs), or newer products using blockchain technology, like [NBA Topshot](https://nbatopshot.com/). 

![](/files/-Mh_QejZxkwo9EYzS-7j)

There is a set of packs filled with rewards of varying rarity. A pack can be opened to retrieve the rewards in that pack. What determines how rare a particular reward is, boils down to how many of those rewards exist in total.

$PACK Protocol lets anyone create and sell their own set of packs filled with rewards of varying rarity. In the following sections, we'll discuss what [packs and rewards](/pack-protocol/how-pack-protocol-works/packs-and-rewards.md) are, [how rewards are distributed](/pack-protocol/how-pack-protocol-works/reward-distribution.md) on opening a pack, and [what you can do with your packs and rewards](/pack-protocol/how-pack-protocol-works/market.md).

First, we'll discuss a simple example that explains how $PACK Protocol works.

## Simple example

Let's create a set of packs with three kinds of rewards - 80 **circles**, 15 **squares**, and 5 **stars**. The number of packs created is equal to the sum of the supplies of each reward. So, we now have `80 + 15 + 5` i.e. 100 packs at hand.

![](/files/-Mh_Wf5q_q5Qb7U5CfOX)

On opening one of these 100 packs, the opener will receive one of the pack's rewards - either a **circle**, a **square**, or a **star**. The chances of receiving a particular reward is determined by how many of that reward exists across our set of packs. The chances of receiving a particular reward are calculated as:

`(number of rewards packed ) / total number of packs`

In the beginning, 80 **circles**, 15 **squares**, and 5 **stars** exist across our set of 100 packs. That means the chances of receiving a **circle** upon opening a pack is `80/100` i.e. 80%. Similarly, a pack opener stands a 15% chance of receiving a **square**, and a 5% chance of receiving a **star** upon opening a pack.

The chances of receiving each kind of reward change as packs are opened. Let's say one of our 100 packs is opened, yielding a **circle**. We then have 99 packs remaining, with *79* **circles**, 15 **squares**, and 5 **stars** packed.

For the next pack that is opened, the opener will have a `79/99` i.e. around 79.8% chance of receiving a **circle**, around 15.2% chance of receiving a **square**, and around 5.1% chance of receiving a **star**.