Wei

The smallest part of ether (a type of digital currency that may be used on Ethereum) is called wei. Wei got its name after the person who developed the Crypto++ library Wei Dai. One ether equals 10^18 wei.

Main principles of Wei

With growing popularity and to be more precise with a growing price of cryptocurrencies people take an interest in more simple questions. One of these questions is how to get change out of any of it. It’s quite clear with real money, as it is divided into smaller and fixed units. However, cryptocurrency may be divided into smaller and smaller units. 

As it can be divided, many new transactions appear. In order to identify each transaction and provide an appropriate support for it new names also were invented, thus, people won’t get confused with the naming. Also, it can be converted into real currencies. 

So, small units of ether have their own names, sometimes it literally means the quantity of such pieces. For instance a kwei literally means 1,000 wei as it’s a kilo. Although units’ names are quite clear, their non-official existed as well. Kwei may be called a “babbage” and gwei is a “shannon”.

Units of Ether

Wei isn’t the only unit of ether, there are many different units:

• Milliether. One milliether equals 10^15 wei.
• Microether. One microether equals 10^12 wei.
• Gwei. One gwei equals 10^9 wei.
• Mwei. One mwei equals 10^6 wei.
• Kwei. One kwei equals 10^3 wei.

Why a Wei is called Wei

Wei got its name after a computer engineer who graduated from the University of Washington and worked in the Cryptography Research Group at Microsoft. While working his group were developing and implementing cryptosystems. Wei is also a part of the cypherpunk movement, the movement built the theoretical basis bmoney, this is also cryptocurrency. They promoted the idea of “smart contracts”, in which any procedure doesn’t require a person's involvement. Thus, for his outstanding achievements a wei was called after him.