Preface Special Issue on Storage Systems and HDD Technologies Chiaki Ito Corporate Executive Vice President

In terms of storage capacity, the worldwide storage market is expanding by 70 % per year. This rapid increase is mainly due to the strong growth of IT applications such as banking transactions, electron-ic documentation, and shopping at online music stores, which require more storage capacity than the applications of traditional large enter-prise systems. To be sufficiently accessible to large numbers of users, today’s stor-age systems must offer high performance, high reliability, and high availability as basic features. Furthermore, they must support the multiple CPU/OS platforms being used by recent systems and provide many functions, for example, data backup, archiving, and disaster re-covery, with minimum operation costs. To meet these requirements, we need to energetically promote the development and provision of the ap-propriate software and storage units for our customers. In this special issue, we focus on the storage system technologies that apply to long-term information storage and retrieval. We describe some of Fujitsu’s key storage products, for example, RAIDs, which are the core units of storage systems; storage application software; and a storage virtualization switch. HDD technology is a core element of storage systems, and Fujitsu’s HDDs have received high evaluation marks from the market because of their high reliability. This technology has been evolving year-by-year and is now reaching a turning point. In this special issue, we also describe Fujitsu’s breakthrough technologies for achieving further in-creases in HDD recording density. Fujitsu is a remarkable company that can provide entire system solutions, including storage systems, and we will continue developing new technologies to provide our customers with the solutions they need