Delayed Proof of Work (dPoW) is a security method for second-layer consensus. The goal is to defend blockchains against 51% attacks that could jeopardize the network's integrity. This is accomplished by putting an external Proof of Work (PoW) network's hash rate on top of a network's already-existing consensus mechanism.
The leveraged PoW network can perform regular backups thanks to the dPoW security mechanism. Data can be quickly recovered in the event of a system malfunction or hack. To cause damage of this magnitude, the hacker would have had to successfully breach the leveraged blockchain and wipe out all backups therein.
Blockchains can benefit from the security of a second blockchain by using the dPoW security method. It is particularly helpful for newly created blockchains, which are frequently exposed because of their slow hash rate.