Primary storage covers vendors that offer dedicated products or product lines for solid-state arrays (SSAs) or hybrid storage arrays (or both), and software-defined storage (SDS) software. Hybrid storage arrays include solid-state drive (SSD) and hard-disk drive (HDD) configurations. SSA products are 100% solid-state, technology-based systems that cannot be combined or expanded with HDDs. SSAs and hybrid storage arrays must have a dedicated product name and an associated model number. SDS products are designed to operate on industry-standard, commodity hardware on-premises or in the public cloud. A primary storage product’s foremost purpose is to support response time and input/output per second (IOPS)-sensitive structured data workloads. Typical use cases include mission-critical workloads, such as IBM Db2, Microsoft SQL, Microsoft Exchange and SharePoint, Oracle Databases and applications, SAP HANA, and in-house-developed transactional applications.