The blockchain is often hailed for its immaculate security, its immutability, and the protection of its users’ identities. However, there have been many cases where exchanges have been hacked and cryptocoins have been stolen. These hacks can be attributed to lax security standards not in the blockchain-system itself, but in the management and storage of data such as private access keys. The blockchain itself has proven extremely resilient and as more transactions are added to the chains of cryptocurrencies such as bitcoin, the safer the mechanism becomes.
Key learning objectives:
Can attackers change blockchain history?
Explain why nodes would invest resources/computing power into the blockchain network
What is a 51% attack and why is it unlikely?