Namecoin s a cryptocurrency which also acts as an alternative, decentralized DNS, which would avoid domain name censorship by making a new top level domain outside of ICANN control. The coin is designed to halve every four years with the same cap limit as Bitcoin of 21,000,000. With the domain registry service a small number of NMC will be destroyed so after mining has finished there will still be a deflationary ellement in place. Namecoin was the first coin to switch to merged mining.

It is based on the code of bitcoin and uses the same proof-of-work algorithm. It is limited to 21 million coins. Each Namecoin record consists of a key and a value which can be up to 520 bytes in size. Each key is actually a path, with the namespace preceding the name of the record. The key d/example signifies a record stored in the DNS namespace d with the name example and corresponds to the record for the example.bit website. The content of d/example is expected to conform to the DNS namespace specification. The current fee for a record is 0.01 NMC and records expire after 36000 blocks (~200 days) unless updated or renewed. Namecoins used to purchase records are marked as used and destroyed, as giving the fee to miners would enable larger miners to register names at a significant discount.

• Namecoin can store data within its own blockchain transaction database
• Censorship-resistant top level domain .bit, which is functionally similar to .com or .net domains but is independent of ICANN, the main governing body for domain names
• Identity systems
• Messaging systems
• Personal namespaces
• Notary/timestamp systems
• Alias systems
• Issuance of shares/stocks