Merged mining allows miners to mine on more than one proof-of-work blockchain at the same time, as long as both blockchains have the same mining algorithm.

Every share contributed counts toward the total hashrate of both networks, and as a result, both networks are more secure.

For SHA256, f2pool supports merged mining for Namecoin, Vcash and Elastos. For Scrypt, f2pool supports merged mining for Dogecoin.