Xiaojiang's Miscellany: The Challenge of PB

What is PB? PB stands for PetaByte, which is equivalent to 1 thousand TB or 1 million GB. Why bring this up now? Aren't mainstream hard drives still under 1TB? From the perspective of data storage, that statement isn't wrong. The July issue of Wired magazine gave a few vivid examples to show us that it's quite difficult to fill up 1000TB of capacity.