Describing the world, or a segment of it, is one of the key problems in communication. People of all historic eras have been looking for solutions. An array of remarkable approaches has emerged, like Egyptian engravings used to record historical events, Greek and medieval astronomers' survey of the Universe, or Carl von Linne's taxonomy of the world's living creatures.
There is no "best" technique, especially because different human activities call for different approaches. Art deliberately maintains a wide variety of techniques to communicate subtle impressions, beliefs, or affections; the style of the description is often equally as important as the subject itself. On the other hand, science, especially the natural sciences and technology, is looking for precision, conciseness, and unambiguity instead.
Most scientific description techniques like databases, computer programming languages, or even formal description methods are based on the modeling approach. Still, the most well-known representatives of modeling are graphical description systems. These tools enhance the illustrative, easy-to-understand nature of charts and diagrams with the precision of modeling concepts and rules. Things represented by these models can be as diverse as organizational hierarchy charts, genetic maps, and community sewer network diagrams.
Modeling is not only about description and illustration for human use. Their adherence to rules and patterns makes models different from drawings, figures, or free format textual descriptions. This not only reduces data size and disambiguates interpretation, but also makes the model suitable for automatic processing. For example, given an up-to-date company hierarchy chart, ordering correct business cards for each employee is a very straightforward process.
Second, computers are also suitable for automatic processing of models, thus making maximal use of them. While manual processing is tedious, all kinds of information (lists, reports, executable code, documentation, etc.) can be extracted and formatted from model data "at the press of a button" once the data has been inserted into a computer system.
Finally, information technology is an application area as well as a provider for computer modeling. Designing, building, programming, and configuring computer systems are tasks with a level of complexity that has been previously unseen. Human limits become obvious, and modeling again proves to be instrumental in building reliable systems.
There are are two tutorials presented here. The first tutorial on modeling and the Generic Modeling Environment (GME) takes its application example from the IT domain. Throughout the first tutorial's lessons, a design, configuration, and analysis tool for network infrastructures will be developed. The first tutorial gives an in depth, detailed perspective on GME and modeling. For those users that want a quick, simple tutorial to get up and running with GME in no time at all, there is a second set of tutorial lessons, much shorter than the first. The second tutorial uses the computer science concepts of Finite State Machines (FSM), Signal Flow (SF), and Boolean logic circuits as its application of GME.
GME can export/import from/to XML. Each figure will have a link to an exported XML file containing the GME project data used to create that screenshot for users that want to check their own progress against the author's save files. For more on exporting to XML, see Lesson 7 of the long tutorial.