Page 127 - Trust in ICT 2017
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Trust in ICT                                                2


            language that web browsers use to interpret and compose text, images and other materials into web pages.
            Web browsers can read HTML files and render them into visible or audible web pages. HTML describes the
            structure  of  a website semantically for  presentation,  making  it  a  markup  language,  rather  than
            a programming language. The HTML elements form the building blocks of all websites. HTML allows images
            and objects to be hyperlinked and can be used to create interactive forms. It provides a means to create the
            structured documents by denoting structural semantics for texts such as headings, paragraphs, lists, links,
            quotes, and other items. The language is written in the form of HTML elements consisting of tags enclosed
            in angle brackets like <html>. Browsers do not display the HTML tags and scripts, but use them to interpret
            the contents of the page. HTML can include scripts languages such as JavaScript which affect the behaviours
            of HTML web pages. Web browsers can also refer to cascading style sheets (CSS) to define the look and layout
            of texts and other materials.

            If  the  metadata  is  stored  in  HTML  format,  it  is  very  easy  to  share  on  the  Internet.  The  files
            representing metadata can be grouped into three parts: structured texts from reference points to data, how
            the files can be accessed, and location information of files. HTML prescribes how the text will be formatted
            visually, which fonts will be used and on which place, where the image will be situated, and where the
            heading of the chapter is located, etc. However, it is typical for the descriptions of the documents that they
            can  be  classified  into  various  categories.  These  categories  form  a  certain  hierarchy  depending  on  their
            significance. The differences of content are not always represented visually in formatted documents, but
            they are very important for the mass processing of metadata.

            The data models described above are summarized as follows:
            •       Entity-attribute-value (EAV) models
                    –   Making statements about resources.
                        –   (Examples) XML document type definition (DTD), tag, name, address, etc.

            •       Data serialization models
                    –   File, memory buffer, packets of communication protocol, and time-varying data, etc.
                        –   (Examples) binary/integer/real/exponent/character/string/Boolean/time,
                            vector/matrix/array, 2D/3D graphics, recursive, audio/video stream, etc.
            •       Metadata/schema/markup data models
                    –   Specify the processing to be performed or the related actions (i.e. layout, activate, trigger, and
                        invoke, etc.).
            Data storage

            There was a long history of writing, recording, and storing information. Recording can be done using virtually
            any  form  of energy,  spanning  from  manual  muscle  power  in handwriting,  to  acoustic  vibrations
            in phonographic recording, to electromagnetic energy modulating magnetic tape and optical discs. A storage
            device may hold information. Electronic data storage requires electrical power to store and retrieve data.
            Electromagnetic data may be stored in either an analogue data or digital data on a variety of media. This type
            of  data  is  considered  to  be electronically  encoded data,  whether  it  is  electronically  stored  in
            a semiconductor device. Most electronically processed data storage media (including forms of digital data)
            are considered permanent (non-volatile) storage, that is, the data will remain stored when power is removed
            from the device. In contrast, most electronically stored information is volatile memory while it vanishes if
            power is removed.
            Except for printed data, electronic data storage is easier to revise and may be more cost effective than
            alternative methods due to smaller physical space requirements and the ease of replacing (rewriting) data
            on the same medium. However, the durability of printed data is still superior to that of most electronic
            storage media. The durability limitations may be overcome by the ease of duplicating (backing-up) electronic
            data. In this digital age, the long-term durability may be more significant since more than several zeta-bytes
            of the storage capacity may be needed within few years.
            The information files stored on millions of servers constitute educational, cultural, and scientific resources.
            "Web culture" is characterized by the extreme rapidity of data-flows and rapid obsolescence. The average

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