What is Ethereum's Berlin hard fork?

Ethereum’s Berlin Hard Fork is the next upcoming update to the Ethereum Network. After being officially announced on March 8th, the Ethereum Foundation laid out the rough roadmap for how the Ethereum Berlin Hard Fork would become realized.

Could an Ethereum hard fork be a spanner in the works?

An Ethereum hard fork, however, could be a spanner in the works. If contracts held to be inviolable can effectively be overturned by a collective decision to run new software, what guarantee do financial institutions have that their transactions and funds are secure?

What is Ethereum Classic?

They went on to form Ethereum Classic ↗. The Homestead fork that looked to the future. It included several protocol changes and a networking change that gave Ethereum the ability to do further network upgrades. Official improvements included in this fork.

What is staking in Ethereum?

After the Merge, when the Beacon Chain (also known as the consensus layer) and the original Ethereum blockchain (also known as the execution layer) combined to form the current PoS Ethereum blockchain, staking became the only method of creating, validating, and securing blocks on the network.