Currency

The economy is based around three main items..

Value:1 - Symbol: s - Silver Coin, also known as silver. Can be traded with iron nuggets at a bank. This is the base/lowest unit of currency. If someone says a number like give me 1000, it means silver. This is also what shows up in your balance and is used for towny prices.
Value: 10 Symbol: g - Gold Coin, also known as gold. Can be traded with iron bars at a bank. This is the main currency.
Value: 100 Symbol: e - Emerald. Can be mined in the dark worlds.
Gold is used as a major currency, silver as a minor, and emeralds a large currency. Player shops will accept gold (coins) and silver as currency. Otherwise you can make a trading-type player shop and trade for whatever you want.

There are also other different forms of currency.

Ender Pearl 0.25
Silver Coin 1
Gold Nugget 5
Gold Coin 10
Gold Bar 50
Emerald 100

You can use a bank to convert these currencies free of charge.

IMPORTANT

DO NOT TURN INGOTS INTO NUGGETS IN THE CRAFTING TABLE UNLESS YOU REALLY WANT NUGGETS. IRON INGOT IS WORTH 10, NUGGET WORTH 1, YOU WILL ONLY GET 9 NUGGETS AND LOSE MONEY. SAME FOR GOLD!I IF YOU WANT TO EXCHANGE DO IT WITH THE BANK NPC!

What can you do in a bank?

Right-Click the sign to exchange your currencies free of charge.
Store your currency safely, and withdraw it from another location.
Exchange iron and gold for currency by right clicking the banker and browsing through the options.
Buy iron or gold with currency
Ender chests can only be found in banks
For towny (Towns and nations), you must have currency in the bank to be able to deposit it into your town or nation. Withdrawls, likewise, end up in your bank account which can be checked using /bal.

How to use a bank

"Buy" means to withdraw. "Sell" means to deposit. Use the NPC to convert your iron bars or leftover nuggets into currency, right click the sign for the bank.

Creating your own bank.

Check the Guides section.

Free Trade

Trasactions with other players are done using the trading system, check the commands for help. The aether is the official spot where you will find players selling or buying items verbally, and is a good meeting spot for trades.