Computer

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A computer is basically a machine that performs two basic functions: running very quickly a sequence of instructions (a program) and store and retrieve large amounts of information (data). Accordingly, a computer can be characterized by its operating speed (measured in Hertz or cycles per second), the type of instructions that can be executed (this determines the type of computer) and the capacity of its memory (measured in bytes) .

HISTORY OF COMPUTER

The first mechanical calculating machine, a precursor of the digital computer was invented in 1642 by French mathematician Blaise Pascal. That device using a series of wheels ten teeth in each tooth representing a digit from 0 to 9. The wheels were connected so that numbers could be added making advance the correct number of teeth. In 1670 the German philosopher and mathematician Gottfried Wilhelm Leibniz perfected this machine and invented one that could also multiply.

The French inventor Joseph Marie Jacquard, in designing an automatic loom, used thin wooden plates perforated to control the fabric used in complex designs. During the 1880s the American statistician Herman Hollerith conceived the idea of using perforated cards like Jacquard plates, to process data. Hollerith managed to compile statistical information for the census of 1890 US using a system that pretended to punch cards over electrical contacts.

The Analytical Engine

Also in the nineteenth century British mathematician and inventor Charles Babbage elaborated the principles of the modern digital computer. He invented a series of machines, such as differential machine designed to solve complex mathematical problems. Many historians consider Babbage and his partner, the British mathematical Augusta Ada Byron (1815-1852), daughter of the English poet Lord Byron, as the true inventors of the modern digital computer. The technology of the time was not able to transfer their successful practice concepts; but one of his inventions, the Analytical Engine, already had many of the features of a modern computer. Including a current inflow or as a package of punch cards, a memory for storing data, a processor for math operations and a printer for permanent registration.

early computers

Analog computers were first built in the early twentieth century. The first models calculations performed by rotating shafts and gears. With these machines numerical approximations too difficult to be able to be resolved by other methods equations they were evaluated. During the two world wars analog systems were used, later first mechanical and electrical, to predict the trajectory of the torpedoes on submarines and remote operation of pumps in aviation.

electronic Computers

During World War II (1939-1945), a team of scientists and mathematicians working at Bletchley Park, north London, which created the first fully electronic digital computer was considered: the Colossus. By December 1943 the Colossus, which incorporated 1,500 valves or vacuum tubes, was already operational. It was used by the team led by Alan Turing to decode encrypted radio messages from the Germans. In 1939 and independently of this project, John Atanasoff and Clifford Berry had already built a prototype electronic machine at Iowa State College (USA). This prototype and subsequent investigations were carried out in anonymity, and later were overshadowed by the development of Calculator and Numerical Integrator digital electronic (ENIAC) in 1945. The ENIAC, which according showed evidence was based largely on the 'computer 'Atanasoff-Berry (ABC, which stands for Electronic Numerical Integrator and Computer), obtained a patent that expired in 1973, several decades later.
The ENIAC contained 18,000 vacuum tubes and had a speed of several hundred multiplications per minute, but his program was connected to the processor and must be modified manually. a successor to the ENIAC was built with storage program that was based on the concepts of Hungarian-American mathematician John von Neumann. The instructions are stored within a call memory, freeing the computer speed limitations of paper tape reader during execution and allowed to solve problems without reconnecting to the computer.

In the late 1950s the use of transistor in computers marked the advent of smaller, faster and more versatile than machines with valves allow logical elements. As transistors use much less energy and have a longer service life, the birth of their development more sophisticated machines, which were called computers or computers second generation was due. The components are made smaller and the spaces between them, so the manufacture was cheaper system.

Integrated circuits

In the late 1960s came the integrated circuit (IC), which enabled the fabrication of various transistors on a single silicon substrate in which the interconnecting cables were soldiers. The integrated circuit allowed a further reduction of the price, size and error rates. The microprocessor became a reality in the mid-1970s, with the introduction of circuit large scale integration (LSI, which stands for Large Scale Integrated) and, later, with the circuit of large scale integration (VLSI, acronym for Very Large Scale Integrated), with several thousand soldiers interconnected transistors on a single silicon substrate.
HARDWARE
Components and Hardware devices are divided into Basic and Supplementary Hardware Hardware
Basic Hardware: it is the fundamental and essential parts for the computer to function as: Motherboard, monitor, keyboard and mouse.
The Supplementary Hardware: are those non-essential additional devices such as: printer, scanner, digital video camera, webcam, etc.
RAM
RAM memory is used in a computer for temporary storage and work (not mass). In the RAM information, data and programs Processing Unit (CPU) reads and executes processes is temporarily stored. RAM is known as the main memory of the computer, as well as "Central or Work"; Unlike called auxiliary memory, secondary or mass storage (such as hard drives, solid state drives, magnetic tape or other memories).
RAMs are commonly volatile; which means that quickly lose their contents to discontinue power.
PERIPHERALS
It is understood by peripheral units or devices that allow the computer to communicate with the outside, that is, both enter and externalize information and datos.10 Peripherals are those that allow operations known as input / output (I / S ).
Although strictly considered "accessories" or non-essential, many of them are essential for the proper functioning of modern computer; for example, keyboard, hard drive and monitor are now essential elements; but they are not a scanner or plotter. To illustrate this point: in the 80s, many of the first personal computers were not using hard drive or mouse (or mouse), they had only one or two floppy drives, keyboard and monitor as unique peripherals.
INFORMATION INPUT DEVICES (E)

In this category are those that allow the entry of information, generally from some external source or by the user. Input devices provide the primary means for transferring to the computer (more properly to the processor) information from any source, whether local or remote. They also allow performing the essential task of reading and load into memory the operating system and applications or programs, which in turn put operating the computer and make it possible to perform different tasks.
Among the input devices can include: keyboard, mouse or mouse, scanner, microphone, webcam, optical readers barcode, Joystick, CD drive, DVD or BluRay (reading only) acquisition boards / data conversion , etc.
They can be considered as essential for operation, (so as computing today is conceived) to keyboard, mouse and a disc drive device; since only with them the hardware can be operational for a user. The others are rather accessories, but today can be so much need that are considered an essential part of the whole system.
INFORMATION OUTPUT DEVICES (S)
They are those that allow issuing or outputting the information resulting from the operations performed by the CPU (processing).

Output devices provide the primary means to externalize and communicate information and processed data; either the user or another external source, local or remote.
The most common devices of this group are the classic monitors (no touch screen), printers, and speakers.
Among the output peripherals it can be regarded as essential to system operation, to monitor. Others, while accessories are extremely necessary for a user to operate a modern computer.
MIXED DEVICES (E / S INFORMATION)
Are those devices that can operate both ways: both input and output typically can be mentioned as mixed peripheral or input / output: hard disks, floppy disks, magnetic tape, reading and CD / DVD discs ZIP, etc. Also fall in this range, with subtle difference, other units, such as flash memory cards or solid state drive, network cards, modems, capture cards / video output, etc.
While you can classify the pendrive (memory stick), flash memory or USB memory or SSDs in the category of memories, they are commonly used as mass storage devices; being all category Input / Output
Mass storage devices are also known as "Memoirs Secondary or Auxiliary". Among them, without doubt, the hard disk has a special place because it is the most important at present, which hosts the operating system, all applications, utilities, etc. used by the user; besides having sufficient capacity to house information and data in large volumes virtually indefinitely. Web servers, email and network with databases, hard drives use large capacities and with technology that allows them to work at high speeds as well including SCSI normally capacity RAID data redundancy; even they use hybrid technologies: hard drive and solid state drive, which greatly increases its efficiency. The most current interfaces used in hard drives are IDE, SATA, SCSI and SAS; and solid state drives are SATA and PCI-Express because they need large bandwidths.
(Not the classic monitor) touch screen is a device that is considered mixed, as well as displaying information and data (output) can act as an input device, replacing, for example, some features of the mouse or keyboard.

SOFTWARE
The Software is the logical and intangible support that allows the computer to perform intelligent tasks, directing the physical components or hardware with instructions and data across different types of programs.

SOFTWARE RANKINGS

* Operating systems
* Software General Purpose
* Programming languages

OS

It is one who controls and manages the computer has three major functions:

* Coordinate and manipulates the computer hardware, such as memory, printers, disk drives, keyboard or mouse.
* Manage files in various storage devices such as floppy disks, hard disks, CDs or tapes, and manages hardware errors and data loss.

The functions of the operating system you have:

* Accept all work and hold them until their completion.
* Interpretation of commands: Interprets commands that allow the user to communicate with the computer.
* Resource control: Coordinates and manipulates the computer hardware, such as memory, printers, disk drives, keyboard or mouse.

CHARACTERISTICS OF OPERATING SYSTEMS

* Convenience: making it more convenient to use a computer.
* Efficiency: allows computer resources are used as efficiently as possible.
* Ability to evolve: be constructed so as to permit the development, testing or effective introduction of new system functions without interfering with service.
* Responsible for managing the hardware: handles better manage the resources of the computer in terms of hardware is concerned, that is, assign each process a portion of the processor to share resources.

GENERAL USE SOFTWARE

The software commonly used are those that solve a variety of problems of the same type, very different companies or individuals, with adjustments made by a user, examples: word processors, database managers, spreadsheets, etc.
The utility software provides the structure for a large number of business, scientific and personal applications. The spreadsheet software, computer-aided (CAD), word processing, management of databases, design belongs to this category. Most utility software is sold as a package; ie, with software and user-oriented (reference manual keyboard templates, documentation etc.

APPLICATION SOFTWARE

The application software is designed and written for specific personal, business or scientific work such as payroll processing, management of human resources or inventory control. All these data application is processed (receiving material) and generate information (payroll records) to the user.

The software application addresses the various tasks for which computers are used. Also it carries out tasks of word processing, database management and the like.

The Word Processor, in computing, is an application used for manipulating text-based documents. It is the electronic equivalent of paper, pen, typewriter, eraser and dictionary. In principle, word processors were used in specifically dedicated to this task machines; today are used in computers or general purpose computers, in which the word processor is just one of the applications installed.

PROGRAMMING LANGUAGE
Programming languages are tools that allow us to create programs and software. Among them are the phi, Visual Basic, Pascal, Java, etc ..
A computer operates under control of a program which must be stored in the memory unit; such as the hard disk.
Programming languages facilitate programming task, as they have suitable forms that allow to be read and written by people in turn are independent of the computer model used.
Programming languages are independent of computers to use.
There are strategies that allow a computer to run a program in a symbolic programming language. Language processors are programs that allow processing information in text form, represented in symbolic programming languages.

THE INTERNET
Internet is a decentralized set of interconnected communications networks that use the family of TCP / IP protocols, ensuring that the heterogeneous physical networks that compose function as a single logical network, worldwide. Its origins date back to 1969, when the first connection of computers, known as ARPANET, between three universities in California and one in Utah, United States was established.

One of the services that most successful on the Internet has been the World Wide Web (WWW or "the Web"), to the extent that it is common confusion between the two. The WWW is a set of protocols that allows, in a simple, remote consultation hypertext files. This was a later development (1990) and uses the Internet as the transmission medium.

HISTORY OF THE INTERNET
Its origins date back to the 1960s, within ARPA (now DARPA) in response to the need for this organization to seek better ways to use the computers at the time, but faced with the problem that the leading researchers and laboratories wanted have their own computers, which was not only more expensive, but caused a duplication of efforts and resources. Thus was born ARPANET (Advanced Research Projects Agency Network or Agency Network for Advanced Research Projects United States), which gave us the layout of an initial network of high-speed communications to which were integrated other government institutions and networks academic during the 70s.

INTERNET ACCESS
Common methods of Internet access in homes include dial-up, fixed broadband (via coaxial cable, fiber optic cable or copper), Wi-Fi, satellite and cell phones with 3G / 4G technology. Public places to use the Internet include libraries and Internet cafes, where computers with Internet connection are available. There are also Internet access points in many public places such as airport lounges and coffee shops in some cases only for short-term uses. various terms, such as "Internet kiosk", "public access terminal", and "Web payphone" are used. Many hotels now also have public terminals, which usually fee-based. These terminals are accessed for use by multiple clients, such as ticket booking, bank deposit, online payment etc. Wi-Fi provides wireless access to computer networks, and therefore can do so to the Internet itself. Hotspots they recognize this right includes Wi-Fi cafes, where would-be users need to bring their own wireless devices such as a laptop or PDA. These services may be free for all, free to customers only, or fee. An access point does not have to be limited to a confined place. A whole campus or park, or even an entire city can be activated.
DOMAIN NAMES
The Internet Corporation for Assigned Names and Numbers (ICANN) is the authority that coordinates the assignment of unique identifiers on the Internet, including domain names, Internet Protocol addresses, port numbers and protocol parameters. A unified global name (ie, a system of unique names to support each domain) is essential for the Internet to function.
ICANN is headquartered in California, supervised by an International Board commercial technical communities, academia and NGOs. The US government continues to have a privileged role in approved in the Domain Name System changes. As the Internet is a distributed network comprising many voluntarily interconnected networks, Internet, as such, it has no body to govern it.
MODERN USES
The modern Internet allows greater flexibility in working hours and location. With the Internet you can access almost anywhere, through mobile Internet devices. Mobile phones, datacards, handheld game consoles and cellular routers allow users to connect to the Internet wirelessly. Within the limitations imposed by small screens web and other limited facilities of these handheld devices, Internet services, including email and may be available to the general public. Internet providers may restrict the services offered and mobile data charges may be significantly higher than other access methods.
You can find teaching materials at all levels, from kindergarten to post-doctoral is available from websites. Examples range from CBeebies, through secondary school and revision guides, virtual universities, access to high-end academic literature through the likes of Google Scholar. For distance education, help with homework and other assignments, self-guided learning, whiling the time, or just find out more about an interesting fact, it has never been easier for people to access educational information any level, from anywhere. The Internet in general is an important facilitator of both formal and informal education.
The low cost and nearly instantaneous sharing of ideas, knowledge and skills have made collaborative work dramatically easier, with the help of collaborative software. Chat, either in the form of IRC chat room or channel, through an instant messaging system, or a web social networking site, it allows colleagues to stay in touch in a very convenient way when working on their computers during the day. Messages can be exchanged more quickly and conveniently form through the mail. These systems may allow files to be exchanged, drawings and images to be shared, or voice and video contact between team members.
SOCIAL IMPACT
Internet has a profound impact on the world of work, leisure and knowledge worldwide. Thanks to the Web, millions of people have easy and immediate access to a vast and diverse amount of online information. An example of this is the development and distribution of software collaboration Free / Libre / Open-Source (FLOSS) such as GNU, Linux, Mozilla and OpenOffice.org.

Compared to encyclopedias and traditional libraries, the Web has enabled a sudden and extreme decentralization of information and data. Some companies and individuals have adopted the use of weblogs, which are used largely as updatable daily. Some commercial organizations encourage staff to incorporate their areas of expertise on their sites, hoping to impress visitors with expert knowledge and free information.
Internet has reached many of the homes and businesses in rich countries. In this respect it has opened a digital divide with the poor countries, where the penetration of the Internet and new technologies is very limited for people.
However, over time it has been expanding access to the Internet in almost all regions of the world, so it's relatively easy to find at least 2 computers connected in remote regions.
From a cultural perspective of knowledge, the Internet has been an asset and a liability. For people who are interested in other cultures, the Net provides a significant amount of information and interactivity that would be unavailable otherwise.
WEB BROWSER
A browser or web browser (English, web browser) is an application that operates over the Internet, playing file information and websites so that they can be read (and this network is found through links or hyperlinks).

The basic functionality of a web browser is to allow the display of text documents, possibly with embedded multimedia resources. Documents can be located on the computer where the user is, but may also be any other device that is connected to the user's computer or over the Internet, and have the resources necessary for the transmission of documents (a software Web server).

These documents, commonly called web pages, have hyperlinks that link a portion of text or an image to another document, usually related to the text or image.

SEEKERS
A search engine is defined as the computer system that indexes files stored on web servers when information is requested on a topic. By keywords, scanning is performed and the search engine displays a list of addresses with related topics. There are different ways of classifying searchers according to the polling process they perform. The most common classification divides them into: thematic indexes or directories, search engines and metasearch engines.
SEARCH ENGINES
This type of search engines are the most commonly used, based on applications called spiders ( "spiders") or robots, seeking information based on written words, making a collection on the content of the pages and showing as a result those that contain the word or phrase somewhere in the text.
metasearch
The metasearch engines are systems that locate information in the most used search engines, conduct an analysis and select their own results. They have a database, so do not store web pages and perform an automatic search databases of other search engines, which takes a certain range of records with the most relevant results so we can have the necessary information.