Wednesday, October 31, 2012

Best & Economical Laser Printer of 2012

HP LaserJet Pro P1102 Printer
Personal Black and White Laser Printers

HP LaserJet Pro P1102 Printer (CE651A)

Affordable, wireless HP LaserJet printing from virtually anywhere in the home or office with several users.[1][2] Print at up to 19 ppm letter/18 ppm A4 with no need for extra wires. Built-in energy-saving features help save money and resources.
Ideal for business users with home or small offices who want an affordable HP LaserJet printer.

Features

Print wirelessly in your home or office.[1][2]

  • Network the printer without extra cables, using 802.11 b/g wireless networking.[1][2]
  • Print up to 19 ppm letter/18 ppm A4.
  • Start and finish printing sooner with Instant-on Technology.
  • Print on a wide variety of media, using the 150-sheet paper tray and 10-sheet priority input slot.[3]

Experience easy, reliable HP LaserJet printing.

  • Install in a flash—no CD required—using HP Smart Install.[4]
  • Set up and start printing right away with an easy-to-use, intuitive control panel.
  • Receive consistent results with Original HP cartridges and easily reorder with HP SureSupply.[5]
  • Get the services, solutions, software and support of HP Total Care.

Reduce your impact and protect your bottom line.

  • Conserve energy with Instant-on Technology and save even more with HP Auto-On/Auto-Off Technology.[6]
  • Reduce wasted paper by printing only the content you want, using HP Smart Web Printing.[7]
  • Save space with an ultra-compact printer with a sleek, industrial design.
  • HP helps reduce your impact—less packaging, plus free cartridge recycling with HP Planet Partners.[8]

Create professional, cost-effective prints.

  • Produce professional-quality business prints with bold, crisp text and sharp images.
  • Receive improved print quality with HP FastRes 1200.[9]
[1] Wireless printing is only available on the HP LaserJet Pro P1102w Printer.
[2] Wireless performance is dependent upon physical environment and distance from access point.
[3] 10-sheet priority input slot is only available on the HP LaserJet Pro P1102w Printer.
[4] HP Smart Install works with Windows only.
[5] Program features and availability may vary by country. For more information, visit www.hp.com/learn/suresupply.
[6] HP Auto-On and Auto-Off capabilities subject to printer and settings.
[7] To use this feature, you need Microsoft Internet Explorer 6.0–8.0.
[8] HP print cartridge return and recycling is available in 49 countries and territories around the world, covering 88% of the addressable market; see www.hp.com/recycle for details.
[9] HP FastRes 1200 provides the best print quality setting for this device. Choose HP FastRes 600 for fast printing. 

 Specifications

Print speed black:

Normal:Up to 18 ppm

(Measured using ISO/IEC 24734, excludes first set of test documents. For more information see http://www.hp.com/go/printerclaims. Exact speed varies depending on the system configuration, software application, driver, and document complexity. )
First page out (ready)

Black:As fast as 8.5 sec
Print quality black (best)
  • Up to 600 x 600 x 2 dpi (1200 dpi effective output)
Duty cycle (monthly, letter)
Up to 5000 pages;
(Duty cycle is defined as the maximum number of pages per month of imaged output. )
Duty cycle (monthly, A4)
Up to 5000 pages
(Duty cycle is defined as the maximum number of pages per month of imaged output. )
Recommended monthly page volume
250 to 1500
Recommended monthly page volume note
HP recommends that the number of printed pages per month be within the stated range for optimum device performance, based on factors including supplies replacement intervals and device life over an extended warranty period.
Print technology
  • Laser
Processor speed
266 MHz
Print languages
Host-based printing
Display
  • None

Connectivity

HP ePrint capability
No
Wireless capability
  • Optional, enabled with purchase of a hardware accessory
Connectivity, standard
  • 1 Hi-Speed USB 2.0
Connectivity, optional
  • Compatible HP Jetdirect print servers: HP Jetdirect ew2500 802.11b/g Wireless Print Server J8021A
Network ready
Optional
Minimum system requirements
Microsoft® Windows® 7 (32-bit/64-bit): 1 GB RAM; Windows Vista® (32-bit/64-bit), Windows® XP, Windows® Server 2008 (32-bit/64-bit), Windows® Server 2003: 512 MB RAM; all systems: 350 MB free hard disk space, CD-ROM drive, USB port;
Mac OS X v 10.4, 10.5, 10.6; 256 MB RAM; 150 MB available hard disk space; CD-ROM drive; USB port
Compatible operating systems
  • Microsoft® Windows® 7 (32-bit/64-bit), Windows Vista® (32-bit/64-bit), Windows® XP (32-bit/64-bit), Windows® Server 2008 (32-bit/64-bit), Windows® Server 2003 (32-bit/64-bit), Mac OS X v 10.4, v 10.5, v 10.6, Linux (see http://www.hplip.net for current)

Memory specifications

Memory, standard
2 MB
Memory, maximum
2 MB
Hard disk
  • None

Paper handling

Paper handling input, standard
  • 150-sheet input tray
Paper handling output, standard
  • 100-sheet output bin
Duplex printing
Manual (driver support provided)
Media sizes supported
A4; A5; A6; B5; postcards; envelopes (C5, DL, B5)
Media sizes, custom
150-sheet input tray: 147 x 211 to 216 x 356 mm
Media types
Paper (laser, plain, photo, rough, vellum), envelopes, labels, cardstock, transparencies, postcards
Supported media weight
60 to 163 g/m²
Finished output handling
  • Sheetfed

Power and operating requirements

Power
Input voltage 115 to 127 VAC (+/- 10%), 60 Hz (+/- 2 Hz), 12 amp; 220 to 240 VAC (+/- 10%), 50 Hz (+/- 2 Hz), 6.0 amp
Power consumption
360 watts (printing), 1.4 watts (ready), 0.9 watts (auto-off), 0.6 watts (manual-off)
(Values subject to change. See http://www.hp.com/go/ljp1100_regulatory for current information. Power numbers are the highest values measured using all standard voltages.)
Energy efficiency
  • ENERGY STAR® qualified
Operating temperature range
15 to 32.5ยบ C
Operating humidity range
  • 30 to 70% RH

Dimensions and weight

Minimum dimensions (W x D x H)
349 x 238 x 196 mm
Maximum dimensions (W x D x H)
349 x 410 x 228 mm
Weight
5.2 kg
Package dimensions (W x D x H)
400 x 250 x 298 mm
Package weight
6.35 kg


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Hacker (computer security)

Hacker (computer security)

From Wikipedia, the free encyclopedia
Jump to: navigation, search

Hacker means someone who finds weaknesses in a computer or computer network, though the term can also refer to someone with an advanced understanding of computers and computer networks.[1] Hackers may be motivated by a multitude of reasons, such as profit, protest, or challenge.[2] The subculture that has evolved around hackers is often referred to as the computer underground but it is now an open community.[3] While other uses of the word hacker exist that are not related to computer security, they are rarely used in mainstream context. They are subject to the long standing hacker definition controversy about the true meaning of the term hacker. In this controversy, the term hacker is reclaimed by computer programmers who argue that someone breaking into computers is better called a cracker,[4] not making a difference between computer criminals (black hats) and computer security experts (white hats). Some white hat hackers claim that they also deserve the title hacker, and that only black hats should be called crackers.

History

Bruce Sterling traces part of the roots of the computer underground to the Yippies, a 1960s counterculture movement which published the Technological Assistance Program (TAP) newsletter.[citation needed] TAP was a phone phreaking newsletter that taught the techniques necessary for the unauthorized exploration of the phone network. Many people from the phreaking community are also active in the hacking community even today, and vice versa.[citation needed]

Classifications

Several subgroups of the computer underground with different attitudes use different terms to demarcate themselves from each other, or try to exclude some specific group with which they do not agree. Eric S. Raymond (author of The New Hacker's Dictionary) advocates that members of the computer underground should be called crackers. Yet, those people see themselves as hackers and even try to include the views of Raymond in what they see as one wider hacker culture, a view harshly rejected by Raymond himself. Instead of a hacker/cracker dichotomy, they give more emphasis to a spectrum of different categories, such as white hat, grey hat, black hat and script kiddie. In contrast to Raymond, they usually reserve the term cracker for more malicious activity. According to (Clifford R.D. 2006) a cracker or cracking is to "gain unauthorized access to a computer in order to commit another crime such as destroying information contained in that system".[5] These subgroups may also be defined by the legal status of their activities.[6]

 

White hat

A white hat hacker breaks security for non-malicious reasons, perhaps to test their own security system or while working for a security company which makes security software. The term "white hat" in Internet slang refers to an ethical hacker. This classification also includes individuals who perform penetration tests and vulnerability assessments within a contractual agreement. The EC-Council, also known as the International Council of Electronic Commerce Consultants has developed certifications, courseware, classes, and online training covering the diverse arena of Ethical Hacking.[6]


Black hat

A "black hat" hacker is a hacker who "violates computer security for little reason beyond maliciousness or for personal gain" (Moore, 2005).[7] Black hat hackers form the stereotypical, illegal hacking groups often portrayed in popular culture, and are "the epitome of all that the public fears in a computer criminal".[8] Black hat hackers break into secure networks to destroy data or make the network unusable for those who are authorized to use the network. They choose their targets using a two-pronged process known as the "pre-hacking stage".
Part 1: Targeting
The hacker determines what network to break into during this phase. The target may be of particular interest to the hacker, either politically or personally, or it may be picked at random. Next, they will port scan a network to determine if it is vulnerable to attacks, which is just testing all ports on a host machine for a response. Open ports—those that do respond—will allow a hacker to access the system.
Part 2: Research and Information Gathering
It is in this stage that the hacker will visit or contact the target in some way in hopes of finding out vital information that will help them access the system. The main way that hackers get desired results from this stage is from "social engineering", which will be explained below. Aside from social engineering, hackers can also use a technique called "dumpster diving". Dumpster diving is when a hacker will literally search through users' garbage in hopes of finding documents that have been thrown away, which may contain information a hacker can use directly or indirectly, to help them gain access to a network.
Part 3: Finishing The Attack
This is the stage when the hacker will invade the preliminary target that he/she was planning to attack or steal. Many "hackers" will be caught after this point, lured in or grabbed by any data also known as a honeypot (a trap set up by computer security personnel).

Grey hat

A grey hat hacker is a combination of a Black Hat and a White Hat Hacker. A Grey Hat Hacker may surf the internet and hack into a computer system for the sole purpose of notifying the administrator that their system has been hacked, for example. Then they may offer to repair their system for a small fee.[8]

Elite hacker

A social status among hackers, elite is used to describe the most skilled. Newly discovered exploits will circulate among these hackers. Elite groups such as Masters of Deception conferred a kind of credibility on their members.[9]

Script kiddie

A script kiddie (or skiddie) is a non-expert who breaks into computer systems by using pre-packaged automated tools written by others, usually with little understanding of the underlying concept—hence the term script (i.e. a prearranged plan or set of activities) kiddie (i.e. kid, child—an individual lacking knowledge and experience, immature).[10]

Neophyte

A neophyte, "n00b", or "newbie" is someone who is new to hacking or phreaking and has almost no knowledge or experience of the workings of technology, and hacking.[8]

Blue hat

A blue hat hacker is someone outside computer security consulting firms who is used to bug test a system prior to its launch, looking for exploits so they can be closed. Microsoft also uses the term BlueHat to represent a series of security briefing events.[11][12][13]

Hacktivist

A hacktivist is a hacker who utilizes technology to announce a social, ideological, religious, or political message. In general, most hacktivism involves website defacement or denial-of-service attacks.

Nation state

Intelligence agencies and cyberwarfare operatives of nation states.[14]

Organized criminal gangs

Criminal activity carried on for profit.[14]

Bots

Automated software tools, some freeware, available for the use of any type of hacker.[14]

Attacks

Computer security
Secure operating systems
Security by design
Secure coding
Computer insecurity
VulnerabilitySocial engineering
Eavesdropping
ExploitsTrojans
Viruses and worms
Denial of service
PayloadsBackdoors
Rootkits
Keyloggers
A typical approach in an attack on Internet-connected system is:
  1. Network enumeration: Discovering information about the intended target.
  2. Vulnerability analysis: Identifying potential ways of attack.
  3. Exploitation: Attempting to compromise the system by employing the vulnerabilities found through the vulnerability analysis.[15]
In order to do so, there are several recurring tools of the trade and techniques used by computer criminals and security experts.

Security exploits

A security exploit is a prepared application that takes advantage of a known weakness. Common examples of security exploits are SQL injection, Cross Site Scripting and Cross Site Request Forgery which abuse security holes that may result from substandard programming practice. Other exploits would be able to be used through FTP, HTTP, PHP, SSH, Telnet and some web-pages. These are very common in website/domain hacking.

Techniques

Vulnerability scanner
A vulnerability scanner is a tool used to quickly check computers on a network for known weaknesses. Hackers also commonly use port scanners. These check to see which ports on a specified computer are "open" or available to access the computer, and sometimes will detect what program or service is listening on that port, and its version number. (Note that firewalls defend computers from intruders by limiting access to ports/machines both inbound and outbound, but can still be circumvented.)
Password cracking
Password cracking is the process of recovering passwords from data that has been stored in or transmitted by a computer system. A common approach is to repeatedly try guesses for the password.
Packet sniffer
A packet sniffer is an application that captures data packets, which can be used to capture passwords and other data in transit over the network.
Spoofing attack (Phishing)
A spoofing attack involves one program, system, or website successfully masquerading as another by falsifying data and thereby being treated as a trusted system by a user or another program. The purpose of this is usually to fool programs, systems, or users into revealing confidential information, such as user names and passwords, to the attacker.
Rootkit
A rootkit is designed to conceal the compromise of a computer's security, and can represent any of a set of programs which work to subvert control of an operating system from its legitimate operators. Usually, a rootkit will obscure its installation and attempt to prevent its removal through a subversion of standard system security. Rootkits may include replacements for system binaries so that it becomes impossible for the legitimate user to detect the presence of the intruder on the system by looking at process tables.
Social engineering
When a Hacker, typically a black hat, is in the second stage of the targeting process, he or she will typically use some social engineering tactics to get enough information to access the network. A common practice for hackers who use this technique, is to contact the system administrator and play the role of a user who cannot get access to his or her system. Hackers who use this technique have to be quite savvy and choose the words they use carefully, in order to trick the system administrator into giving them information. In some cases only an employed help desk user will answer the phone and they are generally easy to trick. Another typical hacker approach is for the hacker to act like a very angry supervisor and when the his/her authority is questioned they will threaten the help desk user with their job. Social Engineering is very effective because users are the most vulnerable part of an organization. All the security devices and programs in the world won't keep an organization safe if an employee gives away a password. Black Hat Hackers take advantage of this fact. Social Engineering can also be broken down into four sub-groups. These are intimidation, helpfulness, technical, and name-dropping.
  • Intimidation As stated above, with the angry supervisor, the hacker attacks the person who answers the phone with threats to their job. Many people at this point will accept that the hacker is a supervisor and give them the needed information.
  • Helpfulness Opposite to intimidation, helpfulness is taking advantage of a person natural instinct to help someone with a problem. The hacker will not get angry instead act very distressed and concerned. The help desk is the most vulnerable to this type of Social Engineering, because they generally have the authority to change or reset passwords which is exactly what the hacker needs.
  • Name-Dropping Simply put, the hacker uses the names of advanced users as "key words", and gets the person who answers the phone to believe that they are part of the company because of this. Some information, like web page ownership, can be obtained easily on the web. Other information such as president and vice president names might have to be obtained via dumpster diving.
  • Technical Using technology to get information is also a great way to get it. A hacker can send a fax or an email to a legitimate user in hopes to get a response containing vital information. Many times the hacker will act like he/she is involved with law enforcement and needs certain data for record keeping purposes or investigations.
Trojan horses
A Trojan horse is a program which seems to be doing one thing, but is actually doing another. A trojan horse can be used to set up a back door in a computer system such that the intruder can gain access later. (The name refers to the horse from the Trojan War, with conceptually similar function of deceiving defenders into bringing an intruder inside.)
Viruses
A virus is a self-replicating program that spreads by inserting copies of itself into other executable code or documents. Therefore, a computer virus behaves in a way similar to a biological virus, which spreads by inserting itself into living cells.
While some are harmless or mere hoaxes most computer viruses are considered malicious.
Worms
Like a virus, a worm is also a self-replicating program. A worm differs from a virus in that it propagates through computer networks without user intervention. Unlike a virus, it does not need to attach itself to an existing program. Many people conflate the terms "virus" and "worm", using them both to describe any self-propagating program.
Key loggers
A key logger is a tool designed to record ('log') every keystroke on an affected machine for later retrieval. Its purpose is usually to allow the user of this tool to gain access to confidential information typed on the affected machine, such as a user's password or other private data. Some key loggers uses virus-, trojan-, and rootkit-like methods to remain active and hidden. However, some key loggers are used in legitimate ways and sometimes to even enhance computer security. As an example, a business might have a key logger on a computer used at a point of sale and data collected by the key logger could be used for catching employee fraud.

Notable intruders and criminal hackers

Notable security hackers

Customs

The computer underground[2] has produced its own slang and various forms of unusual alphabet use, for example 1337speak. Political attitude usually includes views for freedom of information, freedom of speech, a right for anonymity and most have a strong opposition against copyright.[citation needed] Writing programs and performing other activities to support these views is referred to as hacktivism. Some go as far as seeing illegal cracking ethically justified for this goal; a common form is website defacement. The computer underground is frequently compared to the Wild West.[18] It is common among hackers to use aliases for the purpose of concealing identity, rather than revealing their real names.

Hacker groups and conventions

The computer underground is supported by regular real-world gatherings called hacker conventions or "hacker cons". These draw many people every year including SummerCon (Summer), DEF CON, HoHoCon (Christmas), ShmooCon (February), BlackHat, AthCon, Hacker Halted, and H.O.P.E..[citation needed]. Local Hackfest groups organize and compete to develop skills to send a team to a prominent convention to compete in group pentesting, exploit and forensics on a wider scale. In the early 1980s Hacker Groups became popular, Hacker groups provided access to information and resources, and a place to learn from other members. BBS systems like Utopias[19] provided a platform for information sharing via dialup. Hackers could also gain credibility by being affiliated with an elite group.[20]

Hacking and the media

Hacker magazines

The most notable hacker-oriented magazine publications are Phrack, Hakin9 and 2600: The Hacker Quarterly. While the information contained in hacker magazines and ezines was often outdated, they improved the reputations of those who contributed by documenting their successes.[20]

Hackers in fiction

Hackers often show an interest in fictional cyberpunk and cyberculture literature and movies. Absorption of fictional pseudonyms, symbols, values, and metaphors from these fictional works is very common.[citation needed]
Books portraying hackers:
Films also portray hackers:

Non-fiction books

Fiction books

See also


source: wikipedia.com

Ivy Bridge Processors

IntelIntel’s latest computer processors have recently been released in Pakistan. They are called Ivy Bridge CPUs and are the successors to the Sandy Bridge line of Central Processing Units.

Ivy Bridge CPUs are a die shrink of the Sandy Bridge line of CPUs. This means that a newer manufacturing process was used to make Ivy Bridge CPUs. This manufacturing process allows for smaller transistors thereby reducing cost of production and power consumption of the CPUs.
  • Ivy Bridge CPUs perform between 5% and 15% faster than Sandy Bridge CPUs running at the same clock speed.
  • Ivy Bridge CPUs have a faster Integrated Graphics Processor (IGP) compared to Sandy Bridge CPUs. The IGP is around 25% faster.
  • The new CPUs are compatible with existing H61/67 P67 and Z68 chipset motherboards. However, a BIOS upgrade is required for the new CPUs to work.
  • A new line of chipsets has also been introduced for Ivy Bridge CPUs. These are the 7 series chipsets like the H77/Z77. These chipsets support PCI-E 3.0 and USB 3.0.
  • Ivy Bridge CPUs carry the same Core i3/i5/i7 monikers as previous generation Sandy Bridge CPUs. The only difference is that the model numbers begin with a ’3′ instead of a ’2′. So for example the Core i5 3450 is an Ivy Bridge CPU.
  • Only quad core CPUs have been released so far. Dual core i3 CPUs are due to be released in the last quarter of this year.
Ivy Bridge CPUs are slightly faster than the previous generation Sandy Bridge CPUs. That makes them a good choice for new computer builds but a not a worthwhile upgrade for existing systems running Sandy Bridge CPUs.

Information Technology

Information technology

From Wikipedia, the free encyclopedia
Jump to: navigation, search

Information technology (IT) is concerned with the development, management, and use of computer-based information systems.
Humans have been storing, retrieving, manipulating and communicating information since the Sumerians in Mesopotamia developed writing in about 3000 BC,[1] but the term "information technology" in its modern sense first appeared in a 1958 article published in the Harvard Business Review; authors Leavitt and Whisler commented that "the new technology does not yet have a single established name. We shall call it information technology (IT)."[2] Based on the storage and processing technology employed, it is possible to distinguish four distinct phases of IT development: pre-mechanical (3000 BC – 1450 AD), mechanical (1450–1840), electromechanical (1840–1940) and electronic.[1] This article focuses on the latter of those periods, which began in about 1940.


Definition

The Information Technology Association of America has defined information technology (IT) as "the study, design, development, application, implementation, support or management of computer-based information systems",[3] but the term has also been applied more narrowly to describe a branch of engineering dealing with the use of computers and telecommunications equipment to store, retrieve, transmit and manipulate data.[4] Although commonly used to refer to computers and computer networks, IT encompasses other information-distribution technologies such as television and telephones,[5] a wider field more explicitly known as information and communications technology.

History of computers

Devices have been used to aid computation for thousands of years, probably initially in the form of a tally stick.[6] The Antikythera mechanism, dating from about the beginning of the first century BC, is generally considered to be the earliest known mechanical analog computer; it is also the earliest known geared mechanism.[7] Comparable geared devices did not emerge in Europe until the 16th century,[8] and it was not until 1645 that the first mechanical calculator capable of performing the four basic arithmetical operations was developed.[9]
Electronic computers, using either relays or valves, began to appear in the early 1940s. The electromechanical Zuse Z3, completed in 1941, was the world's first programmable computer, and by modern standards one of the first machines that could be considered a complete computing machine. Colossus, developed during the Second World War to decrypt German messages was the first electronic digital computer, but although programmable it was not general-purpose, being designed for a single task. Neither did it store its programs in memory; programming was carried out using plugs and switches to alter the internal wiring.[10] The first recognisably modern electronic digital stored-program computer was the Manchester Small-Scale Experimental Machine (SSEM), which ran its first program on 21 June 1948.[11]



Data storage

Early electronic computers such as Colossus made use of punched tape, a long strip of paper on which data was represented by a series of holes, a technology now obsolete.[12] Electronic data storage as used in modern computers dates from the Second World War, when a form of delay line memory was developed to remove the clutter from radar signals, the first practical application of which was the mercury delay line.[13] The first random-access digital storage device was the Williams tube, based on a standard cathode ray tube,[14] but the information stored in it and delay line memory was volatile in that it had to be continuously refreshed, and thus was lost once power was removed. The earliest form of non-volatile computer storage was the magnetic drum, invented in 1932[15] and used in the Ferranti Mark 1, the world's first commercially available general-purpose electronic computer.[16]
Most digital data today is still stored magnetically on devices such as hard disk drives, or optically on media such as CD-ROMs.[17] It has been estimated that the worldwide capacity to store information on electronic devices grew from less than 3 exabytes in 1986 to 295 exabytes in 2007,[18] doubling roughly every 3 years.[19]

Databases

Database management systems emerged in the 1960s to address the problem of storing and retrieving large amounts of data accurately and quickly. One of the earliest such systems was IBM's Information Management System (IMS),[20] which is still widely deployed more than 40 years later.[21] IMS stores data hierarchically,[20] but in the 1970s Ted Codd proposed an alternative relational storage model based on set theory and predicate logic and the familiar concepts of tables, rows and columns. The first commercially available relational database management system (RDBMS) was available from Oracle in 1980.[22]
All database management systems consist of a number of components that together allow the data they store to be accessed simultaneously by many users while maintaining its integrity. A characteristic of all databases is that the structure of the data they contain is defined and stored separately from the data itself, in a database schema.[20]
The extensible markup language (XML) has become a popular format for data representation in recent years. Although XML data can be stored in normal file systems, it is commonly held in relational databases to take advantage of their "robust implementation verified by years of both theoretical and practical effort".[23] As an evolution of the Standard Generalized Markup Language (SGML), XML's text-based structure offers the advantage of being both machine and human-readable.[24]

Data retrieval

The relational database model introduced a programming language independent Structured Query Language (SQL), based on relational algebra.[22]
The terms "data" and "information" are not synonymous. Anything stored is data, but it only becomes information when it is organised and presented meaningfully.[25] Most of the world's digital data is unstructured, and stored in a variety of different physical formats[26][a] even within a single organisation. Data warehouses began to be developed in the 1980s to integrate these disparate stores. They typically contain data extracted from various sources, including external sources such as the Internet, organised in such a way as to facilitate decision support systems (DSS).[27]

Data transmission

Data transmission has three aspects: transmission, propagation, and reception.[28]
XML has been increasingly employed as a means of data interchange since the early 2000s,[29] particularly for machine-oriented interactions such as those involved in web-oriented protocols such as SOAP,[24] describing "data-in-transit rather than ... data-at-rest".[29]

Data manipulation

Hilbert and Lopez[18] identify the exponential pace of technological change (a kind of Moore's law): machines' application-specific capacity to compute information per capita roughly doubled every 14 months between 1986 and 2007; the per capita capacity of the world's general-purpose computers doubled every 18 months during the same two decades; the global telecommunication capacity per capita doubled every 34 months; the world's storage capacity per capita required roughly 40 months to double (every 3 years); and per capita broadcast information has doubled every 12.3 years.[18]
Massive amounts of data are stored worldwide every day, but unless it can be analysed and presented effectively it essentially resides in what have been called data tombs: "data archives that are seldom visited".[30] To address that issue, the field of data mining – "the process of discovering interesting patterns and knowledge from large amounts of data"[31] – emerged in the late 1980s.[32]

Commercial perspective

Worldwide IT spending forecast[33] (billions of U.S. dollars)
Category2011 spending2012 spending
Computing hardware404423
Enterprise software269290
IT services845864
Telecom equipment340377
Telecom services1,6631,686
Total3,5233,640

Social and ethical perspectives

The field of information ethics was established by mathematician Norbert Wiener in the 1940s.[34] Some of the ethical issues associated with the use of information technology include:[35]
  • Breaches of copyright by those downloading files stored without the permission of the copyright holders
  • Employers monitoring their employees' emails and other Internet usage
  • Unsolicited emails
  • Hackers accessing online databases
  • Web sites installing cookies or spyware to monitor a user's online activities