Apple ACPT Certifications Exam 9L0-402

A hard disk drive (HDD, 9L0-509 also known as hard disk, hard drive, or the now-near-obsolete terms fixed disk, fixed drive, fixed disk drive, hard file) is a digitally encoded non-volatile storage device which stores data on the magnetic surfaces of hard disk platters.

Hard disks were originally developed for use in connection with, or later inside, a single computer. Later, 9L0-402 audio exam as a way of guarding against hard disk failure, they were arranged into configurations such as redundant array of independent disks (RAID). Hard disks are also found in network attached storage (NAS) devices, but for large volumes of data may be most efficiently used in a storage area network (SAN). Over time, applications for hard disk drives have expanded beyond computers to include video recorders, audio players, digital organizers, and digital cameras. In 2005 the 9L0-509 first cellular telephones to include hard disk drives were introduced by Samsung and Nokia.

The capacity of hard drives has grown exponentially over time. With early personal computers, a drive with a 20 megabyte capacity was considered large. In the latter half of the 1990s, hard drives with capacities of 1 gigabyte and greater became available. As of 2006, the "smallest" 9L0-402 dumps desktop hard disk still in production has a capacity of 40 gigabytes, while the largest-capacity internal drives are a 3/4 terabyte (750 gigabytes), with external drives at or exceeding one terabyte by using multiple internal disks. These new internal drives increased their storage capacities with Perpendicular recording.