Namecoin

Namecoin (Symbol: ℕ or NMC) is a cryptocurrency that is mined with bitcoin software as bonus. It is based on the code of bitcoin and uses the same proof-of-work algorithm. Like bitcoin, it is limited to 21 million coins.

Unlike bitcoin, Namecoin can store data within its own blockchain transaction database. The original proposal for Namecoin called for Namecoin to insert data into bitcoin's blockchain directly.[7] Anticipating scaling difficulties with this approach,a shared proof-of-work (POW) system was proposed to secure new cryptocurrencies with different use cases.

Namecoin's flagship use case is the censorship-resistant top level domain, which is functionally similar to   or   domains but is independent of ICANN, the main governing body for domain names.