What Is an ‘ASIC’ and How Does Its Use Impact the Security of a PoW Network?

An ASIC (Application-Specific Integrated Circuit) is a specialized computer chip designed to perform only the hashing calculations required for a specific Proof-of-Work algorithm, making it far more efficient than general-purpose hardware. The use of ASICs can centralize mining power among those who can afford and access the best hardware, potentially lowering the threshold for a 51% attack if the ASIC manufacturing and distribution is concentrated.