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What is Libra?
Bitcoin, or other cryptocurrencies in the encrycurrency community, is usually "mined" by computer systems and is limited to 21 million units.
So how do you really own and spend Libra? Through Libra wallets such as Facebook's Calibra or third parties, it is possible to include Libra Association members like PayPal. The idea is to send money to a friend or pay for anything as easy as sending a message on Facebook.
No member of the Libra Association agrees to provide details about what they will build on the blockchain, but we can take Facebook's Calibra wallet as an example of the basic experience. Calibra will launch alongside Libra coins on iOS and Android in Facebook Messenger, WhatsApp and a standalone app. When users register for the first time, they will be done through KYC (Know Your Customer) process, where they will have to provide ID or Passport and other verification information. They need to conduct customer due diligence and report suspicious activity to the authorities.
If everything goes according to plan, this coin is born next year, is accepted by many places, you can just "buy" an electronic wallet, Calibra style of Facebook for example.
Facebook may also have other plans for Libra. A new subsidiary, called Calibra, will run a wallet that will be necessary in the initial rollout. "Facebook created Calibra, a regulated subsidiary, to ensure separation between social and financial data and to build and operate services on its behalf on top of the Libra network," according to a white paper describing the Libra project. Analysts at RBC Capital Markets say those services will likely include games and commerce.
For a TL;DR of how the crypto-finances work: the number of Libra tokens Digging virtual money Libra will always correspond exactly to the pool of physical currency backing it. When a user transfers money for Libra, new tokens are created. When they cash out, the token is destroyed. The tokens are pegged to a pool of reserve currencies, which the Libra Association can adjust based on world markets to ensure there aren't volatile swings in Libra's value.

What Libra Mean for the Crypto Market
Facebook's token is poised to achieve two very important firsts for cryptocurrency: the first crypto asset launched by a major tech company with a wide global rollout across both the financial world and consumer web services, and the launch of the most high-profile stablecoin ever created.