When I am asked 'What do you do?' I want to tell the asker all about the schematics we produce because they are the most unusual work we do and the most interesting. But they are awfully hard to explain so I am going to have a crack at it here.
How to make a schema: get some information, organise it into categories and define the relationships between the categories. Done. Now you have a framework that represents some aspect of the world.
If this is done graphically you end up with a visual language. There are heaps of these in use everyday. Here are some examples that may look familiar:
Synoptic charts show what weather systems consist of.
Genograms show family relationships and categories of the members.
Route schematics use a framework developed to provide information at a glance.
Diagrams are different. They are used to explain something. They may show how something works, they may be used to show the relationships between things but once they wanders over to show what a system consists of, it becomes a schematic.
This diagram shows how a system works but it doesn't organise the information into categories or define relationships.
Schematics use visual languages to show the components and relationships of a system. The components do not need to be shown in a realistic way. But it should be obvious how each component contributes the the system if the visual language is well designed.
All of this risks over simplification of something that is very complex but explaining the complexity hasn't worked well so far! Now all I need are some flip cards so that I can do a 'show and tell' whenever someone asks me 'What do you do?'.