Resources

A resource is a special kind of item that is used or consumed in trade, crafting, construction, and purchasing. Resources are often stored in a separate inventory system from normal items. They are often treated like generic items and a player may even collect from hundreds up to millions of units of resources. Resources are often indicators of wealth.

Resources can be frozen. When resources are frozen, it cannot be exchanged for and transformed into other forms. Frozen resources are usually investments which provide enhanced ability to progress through the game or produce income of resources for the player.

Currency
A currency is a special resource that is primarily used to purchase items, units, structures, services, and other resources. A currency has no intrinsic value and (usually) no other use. It is simply useful in facilitating exchange of goods and services.

Material
A material is a kind of resource that is used, usually in conjunction of other resources and items, in crafting and construction. The product is usually of higher value than the value of the ingredients used in producing it. The value of a material lies in its rarity, number of products it is used in, and the qualities of the products it produces.

Unlike currency, materials are usually treated as though it is no different from items.

Economies
A resource that moved from one place to another forms an economy. An economy is the flow of resources from source to sink. When there is no flow of resources, there is no economy.

Single-Resource Economies
Single-resource economies are resource systems in which the entire resource cycle revolves around a single resource. Usually a currency, it could also be a building material. This system is usually in place where the resource management is a side-feature like in role-playing games and rogue-likes.

Some games have their entire gameplay revolving around this one resource. In idle games, the main objective of the game is to raise the main resource to ever higher numbers. The accelerating inflow of new resource is often accompanied with accelerating resource expenditures.

Dichotomous Economies
Dichotomous economies are a common resource system. This is a common system in real-time strategy games. In a dichotomous economy, as the name suggests, there are two resources in place: a common resource and an uncommon resource. The common resource is a resource that will be used in almost every facet of gameplay. The player will always need large amounts of it but it will usually very easy to amass a large amount of it. Expenses of the common resource is usually in large increments such as 10 and 100. The common resource is usually the currency or building materials.

The uncommon resource is a rarer resource that is typically used in unlocking better units, upgrades, and structures. The uncommon resource may also be used as a premium currency. Some uncommon resources may be used as means to acquire exclusive and cosmetic items and bonuses. Some games even permit the exchange of real-world currency for in-game premium resources.

Material Economies
Material economies are uncommon resource systems. A material economy revolves around the transformation of materials. In material economies, there are often many resources which is used in a variety of purposes. Materials would be used up and frozen in structures and equipment that increase the income of resources into the system which would then allow the pursuit of more expensive yet rewarding pursuits. Frozen resources usually cannot be transformed or exchanged for other resources.

Games such as Factorio and Minecraft use a material economy. In such games, materials used to produce items that are more useful and valuable than the previous ones.

The Resource Cycle
A resource cycle refers to the flow resources throughout gameplay. The resource cycle is usually modeled after the flow of currency in the real-world. The management of resources can be a very important facet of gameplay. As resources are often regulators of progress, convenience, and fun, making sure the player always has enough but never too little and never too much.

There are two parts of a resource cycle, sources and sinks. A source provides an income of resources to the player and the system. A large amount of activities usually provide an income, especially in role-playing games.

A sink takes and freezes resources from the system, removing the total amount of resources and locking a fraction of it into a form that cannot be transformed into other items. An example of a sink would be a shop. A shop would take resources (usually currency) and exchange it or freeze it into a usable non-transformable form like weapons and tools. A consumable is an excellent sink item as it is not only useful, it also effectively removes the resources that was frozen in the purchase/creation of the item from the system.

In multiplayer games, player-run shops and auction houses are not effective sinks. Player-run shops and auction houses do not remove remove resources from the system, but transfers said resources to another player. Controlling the flow and amount currency in a system is important for regulating inflation.