The Portable hard disk drive is the main, and usually most substantial, data storage hardware device in a computer. The operating system, software titles, and most other files are stored in the hard disk drive.A hard disk drive (sometimes abbreviated as a hard drive, HD, or HDD) is a non-volatile data storage device. It is usually installed internally in a computer, attached directly to the disk controller of the computer's motherboard. It contains one or more platters, housed inside of an air-sealed casing. Data is written to the platters using a magnetic head, which moves rapidly over them as they spin.

Internal hard disks reside in a drive bay, connected to the motherboard using an ATA, SCSI, or SATA cable. They are powered by a connection to the computer's PSU (power supply unit)

Network Storage Keep all your important data in a single location so it’s safe and easy to access, wherever and whenever. A SAN and network-attached storage (NAS) are two different types of shared networked storage solutions. While a SAN is a local network composed of multiple devices, NAS is a single storage device that connects to a local area network (LAN).

A storage area network (SAN) is a dedicated, independent high-speed network that interconnects and delivers shared pools of storage devices to multiple servers. Each server can access shared storage as if it were a drive directly attached to the server. A SAN is typically assembled with cabling, host bus adapters, and SAN switches attached to storage arrays and servers. Each switch and storage system on the SAN must be interconnected.A SAN (storage area network) is a network of storage devices that can be accessed by multiple servers or computers, providing a shared pool of storage space. Each computer on the network can access storage on the SAN as though they were local disks connected directly to the computer.

A term used to refer to storage devices that connect to a network and provide file access services to computer systems. These devices generally consist of an engine that implements the file services, and one or more devices, on which data is stored. NAS uses file access protocols such as NFS or CIFS.

Designers of software applications suited to smaller business environments tend to use file-based systems to meet these goals, particularly those of flexibility, simplicity and ease of management; and there are a wide variety of easy-to-use tools to provide security, and robust backup & recovery.

NAS systems are popular with enterprise and small businesses in many industries as effective, scalable and low-cost storage solutions. They can be used to support email systems, accounting databases, payroll, video recording and editing, data logging, business analytics and more; a wide variety of other business applications are underpinned by NAS systems.

Given the flexibility and popularity of NAS systems, most cloud providers offer NAS services; that makes it possible to mix and match NAS storage systems and cloud services in a business, allowing the potential of optimizing cost, management effort and performance while giving the business complete control over location and security.