There are a number of categories of NAS [network attached storage] and file system companies. First there is the mainstream NAS market for file storage and home directories and file sharing. This includes a mix of operating systems like Unix, Linux, Windows and Novell; there are many different environments available. There are some database environments thrown in, as well. This is where we see companies like NetApp [Network Appliance...
Inc.], Microsoft and EMC [Corp].
NAS is also being used in the area of high-performance computing (HPC), which includes seismic research, satellite imagery, medical imagery and complex engineering design work across a variety of disciplines. Multimedia data is growing fast with video and audio production, editing, rendering and even viewing. The online world is also opening new markets for NAS. These applications often involve large file systems with hundreds of terabytes --potentially petabytes -- of storage capacity. These systems are closely aligned to the business, often touting ease-of-use features that make the storage almost 'invisible' to the organization.
Another big need appears in the area of 'nearline' or archival storage. Data starts off as a dynamic resource where it accessed all the time but quickly becomes a static or persistent resource that rarely changes and is only accessed infrequently. NAS systems are being used to store a lot of this persistent data. These NAS systems must also be easy to manage and highly scalable. The cost must also be lower than Tier 1 storage and include index/search capabilities so that I can Google my storage to access the necessary data quickly and precisely.
Check out the entire NAS FAQ guide.