ICT

Data transfer

Transfer of data [data: information without context, eg a list of students with numbers beside their names is data, when it's made clear that those numbers represent their placing in a 100 metre race, the data becomes information ] files containing pictures (graphics), text, sound, or numbers is possible from one computer to another, one make of hardware [hardware: the physical components of a computer ] to another, and one application to another. This is possible because standard file types and data formats have been developed.

Data does not need to be transfered on physical media [media: The plural form of medium - examples include paint, clay, glass, textiles, photography, print and so on. Wet media includes paints and pens. Dry media includes pencils and charcoals. ], it can be transmitted at rapid speeds around the globe.

Data file types

Data files are stored in a number of formats, the formats depend on which application [application: applications serve a specific purpose, eg Microsoft Word is used for word processing ] created the file to begin with. For example, Microsoft Word stores files as *.doc but Adobe Photoshop stores files in a different format - *.psd. The file extension identifies the file's format.

Opening files of different formats

When data is transferred from one computer to another, the computer receiving the data file may not be able to read the format without the right application installed. For example, an image created in Adobe Photoshop and saved as a *.psd file (Photoshop's format) would not be readable by Microsoft Paint.

This is becoming less of a problem as standardisation matures and applications expand the list of file types they're able to read.

Translating between file types

Data [data: information without context, eg a list of students with numbers beside their names is data, when it's made clear that those numbers represent their placing in a 100 metre race, the data becomes information ] can be stored temporarily in a computer's RAM [Random Access Memory (RAM): Memory that is constantly being written to and read from. It does not retain its contents without a constant supply of power, ie when a computer is turned off, everything stored in its RAM is lost. ] as a means of transfer from one application to another. In Microsoft operating systems [operating system: an interface between hardware, eg a computer, and the user ] this feature is called the clipboard and it can copy data from one application [application: applications serve a specific purpose, eg Microsoft Word is used for word processing ] and paste it into another. Nearly all other operating systems support this functionality.

For example you can create a graph using a spreadsheet [spreadsheet: A spreadsheet is made up of cells, rows and columns. Each cell holds a piece of numeric (numbers) or alphanumeric (text) data. Cells can also contain formulae to calculate their contents. ] application and then use the clipboard to copy the graph to a desktop publishing [desktop publishing: an application that allows text and images to be laid out on a page ] application.

Limitations

  1. Certain elements of one document may not be copiable to another application, eg video.
  2. Some file features (eg text layout and formatting) may be lost in the translation to a different format.

Import and export

file is clicked, drop down menu, option highlighted is 'Export...'

Most applications have the ability to import and export data. Export saves the file in a format that's readable by other applications. Import opens a file created in another application for viewing or editing.

Standard file types

The need to import [import: A good or service which enters a country. ] and export [export: to export a file from an application in a file format that can be read by another application or applications ] data files has led to the development of several standard file types that many applications [application: applications serve a specific purpose, eg Microsoft Word is used for word processing ] can understand. Examples are jpg and gif files for images, and mp3 files for sound; but there are also standard file types for text, movies, and spreadsheet [spreadsheet: A spreadsheet is made up of cells, rows and columns. Each cell holds a piece of numeric (numbers) or alphanumeric (text) data. Cells can also contain formulae to calculate their contents. ] data.

Often an application of a different type can import data, for example, a word processor [word processor: an application used to write, edit and format text ] may be able to import a spreadsheet file.

XML files

Recently program [program: a list of instructions written in a programming language ] developers have started to use the XML [Extensible Markup Language (XML): a general-purpose specification for creating custom markup languages ] web [web: includes all of the web pages accessible via the Internet ] page file format as the standard way to store data, for example, the new Microsoft Office suite makes use of XML. RSS [Really Simple Syndication (RSS): a method for delivering website updates to a user without the user having to visit the website itself ] feeds on the Internet [Internet: a global network connecting millions of computers ] also make use of this format. Such files can be read by any browser [web browser: an application used to browse the Internet or view web pages ] on any computer, making it very easy to transfer data between computers.

Other examples

Other standard file types, such as zip [zip: a file format that takes an existing file or files and compresses them into a single file that's a smaller size ] and pdf [Portable Document Format (PDF): a file format developed by Adobe in an effort to standardise the way documents were shared ], have been developed as ways of distributing data in the most efficient way possible. They do this by compressing it using zip technology or making it possible to read using a freely available downloaded [download: the transfer of a file or files from one computer connected to the Internet to another ] reader application, as is the case with PDF files.

Rapid transfer of data

Files can be easily transferred and shared across the globe using the Internet [Internet: a global network connecting millions of computers ]. A file could be:

  • emailed [email: electronic mail - a message written or typed on a computer and sent electronically rather than by post ] as an attachment [attachment: a file that's 'attached' to an email is called an attachment ]
  • sent over instant messenger [instant messenger: an application that allows users to send instant messages (text) to one another ]
  • downloaded [download: the transfer of a file or files from one computer connected to the Internet to another ] from a website [website: a web page or group of web pages hosted on one web server and viewed in a web browser ]/web server [web server: a computer that serves web pages to users ]
  • accessed over a private network [network: a group of interconnected computers ]

Documents, eg a spreadsheet [spreadsheet: A spreadsheet is made up of cells, rows and columns. Each cell holds a piece of numeric (numbers) or alphanumeric (text) data. Cells can also contain formulae to calculate their contents. ], can be stored on a web server and then accessed via any computer with an Internet connection [Internet connection: a computer's or another internet-enabled device's connection to the Internet ] and a web browser [web browser: an application used to browse the Internet or view web pages ]. Collaborative working is possible too, where multiple people contribute to the same document.

This makes the world very small as far as transfer of data [data: information without context, eg a list of students with numbers beside their names is data, when it's made clear that those numbers represent their placing in a 100 metre race, the data becomes information ] is concerned. It has allowed many companies to outsource some or all of their operations. This is where companies transfer activities such as ticket processing for airlines or telephone banking queries to workers in a country where wages and running costs are relatively low. Often the time difference between the two countries gives even greater convenience.

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