Transcript:

Nowadays, most people are familiar with the concept of a hard disk drive. This incredible electronic storage medium is part of all modern computers, however, whilst they are ubiquitously used, very few appreciate the deeply complex systems that are involved in the technology of a hard drive.

Early computers used punch card technology; a strip of hard paper containing holes that could be fed into a computer to process data. Later, magnetic tape was developed, which was a more efficient method of storing electrical data. Magnetic tape is still the preferred method of backing up the contents of a hard drive. The downside to magnetic tape however, is that it is slow and must be read through a fixed head in a single pass.

Hard disk drives improve upon this inefficiency by using a spinning disc, on which magnetic data can be accessed and read through a moving head, that can read and write data across the entire disk. It is similar to the way a person can play a particular track on a CD or record, by moving the arm to a different part of the disk.

Hard drives differ from CDs however, in that they use multiple disks in order to minimise the time required to find the necessary data. Some more modern drives contain two heads, one for reading data, and another for writing data. Separating these tasks allow higher volumes of data to be written on the disk, increasing the memory capacity of the hard drive.

There are three main ways in which the memory of hard drives has been expanded. Firstly, the data code itself has been ‘tightened’, with more modern coding techniques, allowing more data to be stored in a smaller space. Secondly, the aforementioned separation of head technology has made reading and writing to the disk much faster. Thirdly, the physical distance between the heads has been significantly reduced to as little as 1/5000^th of a human hair. All of these improvements have made access to data much more rapid.

Whilst hard drives are far more common than tape recorders, they are also far more fragile, and can be damaged relatively easily. This can have terrible consequences for the user, whose data may be irretrievably corrupted or lost. Hard drives can be damaged physically by heat, dust, dropping, or via electrical currents due to faulty connections. With due care, hard drives can last a very long time, however, eventually the magnetised coating on the disks break down, and the hard drive will become corrupted.

The future of hard drives is uncertain. Some believe that it would be better to invest in systems for streaming data across networks connected to centralised banks of information storage, thus avoiding the necessity for each personal computer to have its own local hard drive. Personal data files would be stored on a central unit, and protected from damage or corruption by a backup system. As the internet becomes faster and more universal, local storage systems may become less necessary.

Vocabulary bank:

familiar - adj.  well known or easily recognized; within normal everyday experience; common and ordinary; not strange; (usually followed by `with')

concept - noun an abstract or general idea inferred or derived from specific instances

hard disk drive - noun A computer hard disk drive (HDD) is a non-volatile data storage device. Non-volatile refers to storage devices that maintain stored data when turned off.

medium - noun an intervening substance through which signals can travel as a means for communication; a means or instrumentality for storing or communicating information

modern - adj. characteristic of present-day art and music and literature and architecture; being the current stage in its development; relating to a recently developed fashion or style; ahead of the times

ubiquitous - adj. being present everywhere at once

complex - adj. complicated in structure; consisting of interconnected parts

punch card - noun a card perforated according to a code, for controlling the operation of a machine, used in voting machines and formerly in programming and entering data into computers.

process - verb subject to a process or treatment, with the aim of readying for some purpose, improving, or remedying a condition; perform mathematical and logical operations on (data) according to programmed instructions in order to obtain the required information

magnetic - adj. having the properties of a magnet; i.e. of attracting iron or steel

tape - noun memory device consisting of a long thin plastic strip coated with iron oxide; used to record audio or video signals or to store computer information

efficient - adj. being effective without wasting time or effort or expense; able to accomplish a purpose; functioning effectively

method - noun a way of doing something, especially a systematic way

preferred - adj. more desirable than another; preferred above all others and treated with partiality

backup - noun (computer science) a copy of a file or directory on a separate storage device

content - noun everything that is included in a collection

downside - noun a negative aspect of something that is generally positive

head - noun (computer science) a tiny electromagnetic coil and metal pole used to write and read magnetic patterns on a disk

pass - noun one complete cycle of operations (as by a computer)

inefficiency - noun unskillfulness resulting from a lack of efficiency

multiple - adj. having or involving or consisting of more than one part or entity or individual; noun the product of a quantity by an integer

minimise - verb make small or insignificant; represent as less significant or important

necessary - adj. unavoidably determined by prior circumstances; absolutely essential; noun anything indispensable

volume - noun a relative amount; the property of something that is great in magnitude

memory - noun an electronic memory device; 

capacity - noun a specified function; the maximum production possible

expand - verb become larger in size or volume or quantity; make bigger or wider in size, volume, or quantity; extend in one or more directions; exaggerate or make bigger

code - noun (computer science) the symbolic arrangement of data or instructions in a computer program or the set of such instructions

aforementioned - adj. being the one previously mentioned or spoken of

rapid - adj. done or occurring in a brief period of time; characterized by speed; moving with or capable of moving with high speed; noun a part of a river where the current is very fast

fragile - adj. vulnerably delicate; easily broken or damaged or destroyed; lacking solidity or strength and liable to break

consequence - noun having important effects or influence; the outcome of an event especially as relative to an individual; a phenomenon that follows and is caused by some previous phenomenon

irretrievable - adj. impossible to recover or recoup or overcome

corrupted - adj. ruined in character or quality; containing errors or alterations

current - noun a flow of electricity through a conductor

faulty - adj. characterized by errors; having a defect

magnetised - adj. having the properties of a magnet; i.e. of attracting iron or steel

invest - verb provide with power and authority; spend money on

streaming - adj. exuding a bodily fluid in profuse amounts; moving smoothly and continuously; noun the circulation of cytoplasm within a cell

network - noun (electronics) a system of interconnected electronic components or circuits; a system of intersecting lines or channels; an interconnected system of things or people

centralised - adj. concentrated on or clustered around a central point or purpose; drawn toward a center or brought under the control of a central authority

necessity - noun anything indispensable; the condition of being essential or indispensable

local - adj. relating to or applicable to or concerned with the administration of a city or town or district rather than a larger area

file - noun a set of related records (either written or electronic) kept together