Block 1 DATA

This block introduces some simple study techniques in the form of references to the Good Study Guide or The Learner’s Guide. It describes what data is and examines techniques of data acquisition and some general aspects of data storage.

The first unit sets the scene for course. Using a series of short case studies about the applications of computers to a variety of situations, it describes the wide variety of applications in which computers have been used to solve a variety of problems. Such problems range from controlling simple appliances and finding information on the web to the global positioning system and surveying and map-making. Basic terms are introduced and explained, and activities aid students to improve their use of searching mechanisms on the web.

Unit 2 introduces the idea of different modalities (such as sound, language as a written system, graphics). It then examines how meaning is assigned in the form of signs and symbols, and discusses how symbols require the sharing of cultural assumptions for their correct interpretation. Problems of interpretation and misinterpretation are examined as are the concepts of representation and the fitness for purpose of a particular representation. This leads to examining the need for standards, to enable people (or machines) to apply meaning (through interpretation). Representations of text in computing systems, such as ASCII and Unicode are described.

We live in an analogue world, but what can be quantified or encoded digitally becomes simply a stream of bits, which have no inherent meaning. Unit 3 introduces the notion of continuous and discrete data, and analogue and digital forms of encoding. The process of digitization is described using sound, graphics, and examples, such as temperature. We discuss standards for sound as examples.

Many forms of data are now integrated. One of the earliest examples was sound on film. Unit 4 begins with the concept of mark-up languages, as well as setting the stage for Block 2. HTML is a specific example of a mark-up language, which can be used to style paper documents and web pages.

The concept of hypertext to form links between parts of a document and between different documents is explored. The unit asks what is the difference between multiple media and multimedia and then looks at an attempt to extend mark-up languages to include and integrate non-textual representations such as photographs, video and sound using a mark-up language called XML.

The final unit in the block examines the idea of persistent data – data that remains intact even when the computer is shut down – and why this is so important to the use of computers. It also looks at how data can be structured to achieve different purposes for different users.

Access to data requires the identification of a data object, and may require metadata to describe that object. This unit examines the concept of metadata. Large collections of accessible data (such as databases) raise important social and legal issues such as who owns data. Is the owner the person described, the owner of the computer, or some other body (such as the National Health Service or a local education authority)? What sorts of rights does an individual have to control both the content of and access to data about them as a person?

HOME / QUIZ / Course Details / Calendar / Contact Us / Course Description / Copyright notice / The Open University