DATA SECURITYData security is about keeping data safe. Manyindividuals, small businesses and majorcompanies rely heavily on their computersystems
KEY THREATS TO DATA SECURITYData may get: -lost or damaged during a system crash - especially one affecting the hard disk corrupted as a result of faulty disks, disk drives, or power failures -lost by accidentally deleting or overwriting files -lost or become corrupted by computer viruses -hacked into by unauthorized users and deleted or altered -destroyed by natural disasters, acts of terrorism, or war -deleted or altered by employees wishing to make money or take revenge on their employer
KEEPING DATA SECUREMeasures that can be taken to keep datasecure include: -making regular backups of files (backup copies should be stored in fireproof safes or in another building) -protecting yourself against viruses by running anti-virus software -using a system of passwords so that access to data is restricted -safe storage of important files stored on removable disks, eg locked away in a fireproof and waterproof safe
-allowing only authorised staff into certain computerareas, eg by controlling entry to these areas by means ofID cards or magnetic swipe cards-always logging off or turning terminals off and if possiblelocking them-avoiding accidental deletion of files by write-protectingdisks-using data encryption techniques to code data so thatitmakes no apparent sense
Data TransferTransfer of data files containing pictures(graphics), text, sound, or numbers is possiblefrom one computer to another, one make ofhardware to another, and one application toanother. This is possible because standard filetypes and data formats have been developed.Data does not need to be transfered on physicalmedia, it can be transmitted at rapid speedsaround the globe.
DATA FILE TYPESData files are stored in a number of formats, the formats depend on whichapplication created the file to begin with.For example, Microsoft Word stores files as *.doc but Adobe Photoshop storesfiles in a different format - *.psd.The file extension identifies the files format.When data is transferred from one computer to another, the computerreceiving the data file may not be able to read the format without the rightapplication installed.For example, an image created in Adobe Photoshop and saved as a *.psd file(Photoshops format) would not be readable by Microsoft Paint.
TRANSLATING BETWEEN FILE TYPES Data can be stored temporarily in a computers RAM as a means of transfer from one application to another. In Microsoft operating systems this feature is called the clipboard and it can copy data from one application and paste it into another. Nearly all other operating systems support this functionality. For example you can create a graph using a spreadsheet application and then use the clipboard to copy the graph to a desktop publishing application.Limitations: -Certain elements of one document may not be copiable to another application, eg video. -Some file features (eg text layout and formatting) may be lost in the translation to a different format.
RAPID TRANSFER OF DATAFiles can be easily transferred and shared across theglobe using the Internet. A file could be:emailed as an attachmentsent over instant messengerdownloaded from a website/web serveraccessed over a private network
IMPORT AND EXPORT1.Export saves the file in a format thats readable by other applications.2.Import opens a file created in another application for viewing orediting. The need to import and export data files has led to the development of several standard file types that many applications 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 data. Often an application of a different type can import data, for example, a word processor may be able to import a spreadsheet file.
XML FILESRecently program developers have started to use theXML web page file format as the standard way to storedata. Files can be read by any browser on anycomputer, making it very easy to transfer data betweencomputers.Other standard file types, such as zip and pdf (portabledocument format), have been developed as ways ofdistributing data in the most efficient way possible. Theydo this by compressing it using zip technology or making itpossible to read using a freely available downloadedreader application, as is the case with PDF files.