When you think of maps, what exactly do you think?
In essence, a map is a representation of a topology or function. For example, a formula like X = 2Y compares the value of Y to each value of X. Of course, we all know that mathematicians are strange and sometimes difficult to understand, but have you ever seen a schematic map of the metro system (underground railway)? Have you ever seen the same network of rails, which was shown on a more "normal" map of the city in which it is located? Different cards of the same thing may look very different.
When you make a map of a flat area — a “plan” or “elevation” —all is quite simple, but when you try to display a large area, such as the surface of an entire planet, everything can become quite complicated if you want your map to be even. It's very good to make a globe, but try turning the surface of this globe into a flat map! Oh!
However you go about it, you end up with edge effects. When I write this article, I actually do programming cartographic programs designed to create maps of fictional landscapes. I had to study cartographic generators that are included in the free open source strategy (GNU GPL), FreeCiv. Edge effects are very similar to such cards. The cards are mostly rectangular, but you can choose to act as cylinders, wrapping from left to right or top to bottom, or you can even “wrap” in both directions. Most people prefer to use “wrapping” only from left to right and block the top and bottom of the “polar regions”. Such a simplified “packaging” makes quite extreme distortions, although if you try it with a real world map!
Have you ever seen a pedigree chart? This is also some kind of map! Family Relations Card. You may also have seen different diagrams of the evolution of species - a much larger kind of "family tree". These are maps that include time as well as space! You may also have seen “time frames”, which is another type of time map. Maps should not only refer to spatial dimensions!
Consider a dictionary, or index of a book, or even a table of contents of a book. This is also a card. The dictionary is an interesting case, because in some way it is a kind of reverse-look map, in which the words were arranged to fit the map! That is, the words were placed in a sequence defined by the map: the dictionary places the words in alphabetical order for the convenience of their location. The Dewey decimal system used in libraries is also: it helps to show where in the library you can find the book you are looking for.
In essence, the card is a representation of relationships. But it’s also true that the view itself is a map, because if you didn’t have a way to “match” (link) the view to what the view represents, you cannot even understand that the view is a view at all! Think of the paintings by Pablo Picasso or Salvador Dali: photos of things or people, but in some ways distorted. If you distorted the picture even more, it could be so distorted that you could not tell by looking at it, as it was depicted; what it represents. Your eyes and mind should be able to “display” the image on the subject to find out what the image represents.
If you look at the actual .gif or .jpg file or another “image file” used on the Internet to transfer images to your browser; look at it not through an image viewer, such as a browser, but as a sequence of bits or bytes; you are probably very difficult to know what kind of picture. This is because it is a picture card. Your browser knows how to read this card, so it can use it to compare it with your screen.
I could go on wandering around the more and more obscure kinds of cards; but, I hope, you understand that simply “maps” is a wide field, sometimes much wider than many people think that this is so!
