xEcon Core is the main plugin of the package. It handles the database and logs of xEcon entities and transactions; executes the basic commands; and holds the external API of xEcon.
Not to be confused with Minecraft entities, "economic entity" (to avoid confusion, we will call an economic entity an entity and a Minecraft entity MCEntity in this file) refers to anything that has accounts that hold money and can do transactions.
Obviously, a player is one as players are the main target of xEcon transactions. However, xEcon tries to keep every transaction in record. Therefore, when a new player joins and gets money to start with, they actually get money from an account of an entity called Server/Services instead of from nowhere.
Let's look at another example. PocketFactions is a plugin that uses xEcon. It manages "factions" (like organizations of players), where when these factions want to do things like claiming chunks, they have to pay money from the faction's account (instead of from its players'). In this case, factions are entities because they hold accounts to transact with.
To avoid collisions of plugins of different entity types, each entity has a "type" and a "name". For players, it is Player/<player name in lowercase>. If you use a JSON database, players will be saved in entities/Player$<player lowercase name>.json.
As you can see from a database, each entity has "accounts" and "loans". Each account stores some money with a maximum amount and minimum amount. Each loan stores more data. For details, please read documentation about the database.
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