i have two question about username
1- why you ask for money(bitcoin) for register a user name?
2- are you reserve some username? like 2 or 3 char username? if yes why?
@arshia Happy to answer your questions. The fees you are prompted to pay for a username are registration fees. We provide open source software that allows you to create transactions that burn (send to an unrecoverable address) bitcoin and prove that you registered a username with a certain address.
To clarify, these fees are not received by Blockstack. We only provide a protocol and system to search the BTC blockchain for compliant transactions and include any that match in the state of the final system. This allows for an open name registrar that is not controlled by any one party. You are welcome to register any username that is still available.