combination of structure (2), content (1) and context (3). For example, the labels (metadata) on the pump at the gas station clarify the meaning of the data on the display. Technical layers An Information object consists of at least three technical layers. These layers are for (1) presentation, (2) transport and processing, and (3) storing and fixation. They allow recording information in documents and for those documents to be created, saved, edited, viewed and consulted, copied, sent, received and erased. At the same time, these layers are the determining factor for the behaviour of a document. These layers directly affect the other features of a document. The presentation layer will display content, structure and context. This layer also ensures the way the content of a document must behave. The transport layer provides for the processing of bit streams in such a way that the presentation is possible. The storage layer ensures capture and maintenance of bit streams so that processing and presentation are possible. As a practical example, this document is described below, using the above features and layers. This document is displayed on a screen of a PC or tablet or is available as a print on paper. This is possible because in the second layer, conversion of the digital source to the presentation layer (and vice versa) takes place. The digital source is visible as a file on the physical data carrier, but actually presents itself as a bit stream, a row of zeros and ones. Deep inside the technique of storage, the bit stream that makes up the document can be found, but unusable and unrecognisable without the support of software to operate the hardware and to make the document readable. Within a word processor such as MS Word, content, structure and behaviour can be edited, modified, and deleted. Saving this document from MS Word to a PDF/A file, the content and structure are maintained. Only a small portion of the behaviour will be available, such as using links and going to a paragraph or a note with one click. In the paper copy this behaviour is not available, the reader can only browse more easily using his hands and eyes and he can write down his annotations. rienk jonker a perfect match? connecting partners in the labyrinth of information The layers that make up the content cannot be seen separately from the technique. After all, the technique is instrumental in ensuring the use and survival of all components Behaviour and compound documents Behaviour, the fourth of the five characteristics of a document, exists by one or more embedded functionalities in a document. It is in a way part of the technology and is used to generate the presentation of the content and structure. Examples are animations or video and/or audio streams in presentations, generated charts, and execution of macros and formulas in spreadsheets. Another example is an embedded spreadsheet in a text document, which can be opened with just a click of the mouse. Also, hyperlinks - visible and embedded - to other documents or websites are part of the behaviour. The examples are uncountable. It is the element that makes a document dynamic. The situation becomes more complex when there are compound documents that present themselves as one, but are made up of separate components. These components are often different digital documents on their own. In many cases, these individual components are made up of different file formats. A lot of compound documents are already around us, although not everyone recognises them (Ford, 2015). Examples of compound documents are email messages with attachments, digital documents with digital attachments, web pages, digital documents with links to other documents, and games. Dynamic databases with queries and algorithms that are also documents - and that in a sense can be characterised as register - must be placed under the category of compound documents that contain a lot of complex behaviour. From a user's perspective there will not directly be a notion of a compound document. At the level of presentation, the user sees the document as a unit. This presentation depends on the three technical layers. Through the transport/ processing route, the components are retrieved from the storage/fixation (the disks) by one or more applications and digitally forged to a temporally unit which is delivered to the presentation layer. These operations can be considered as behaviour (4). A document is also a compound when links refer to other documents that are stored on internal or external servers as if they were attachments. At an abstract level - although difficult to understand - the total of these files constitutes one document. Examples are web pages. These types of documents are a major preservation challenge for archivists because the management of these information objects is mostly beyond their reach. The complexity lays in the requirement that the presented unit, the total of the components of a compound document, must be preserved and maintained until the date of its disposition. An issue that may arise are broken links. Not all links are permanent: they can be modified, the external files are missing or have disappeared, or other versions of the external files are provided with the same link. Reference rot with content drift and link rot are looming and menacing perspectives. archives in liquid times Layer Meaning 5.1) Presentation Presenting the object to either a machine and/or a human being including the performance of behaviour. 5.2) Transport/processing Transforming the factual technical form (e.g. bit stream) to make the message (content) presentable and therefore usable. E.g. Print to paper, show on digital interfaces like display screens, digital messages in XML between machines. 5.3) Store/Fixation With analogue media like paper: the ink/toner attached to (or in) the medium (paper). Digital data: the bit streams, the zeros and ones on a physical data carrier or on more than one datacarrier which together make up a document. Table 3. Information object - technological layers 84 85

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Jaarboeken Stichting Archiefpublicaties | 2017 | | pagina 44