Mechanical storage, magnetic storage, optical storage, electronic memory – or, better known by associate product names and standards: Punch card, floppy disk, HDD, LTO, CD, DVD, Blu Ray, Flash, SSD, PCM, FeFET, RRAM, STTMRAM: The pace of development of storage technologies is breath taking. And this development enabled new computing disciplines, such as big data, blockchain, or cloud computing, see our corresponding pages. Although the basic physics applied in storing data has been known for many storage applications for a long time: New ideas and technical improvements evolve around domains such as hierarchical storage systems, distributed storage systems, caching strategies, read-write-mechanisms, RAID, key value stores, and corresponding storage software. This is by no means the end of the story. The bare volume of data to be stored calls for innovative approaches in classifying data and assigning data within tiered storage systems.