1. Navigation - Concepts and Tools

Introduction

Where am I?

Have you ever been in a situation where you had to ask yourself "Where am I?" We are sure you were. Everybody gets lost at least once in his/her life.

When you realise that you are lost, what do you do to determine your location? How can you find your way back or the way to continue your journey? Of course we think that it is best to have a map (and to know how to read a map), because with it you are able to determine your position. Since the map shows also the surrounding area of your position, you can determine as well the route that leads to your target location.
If you do not have a map or any other utilities with you that would help to determine your position, you have to orientate you on the objects of your surrounding area (trees, rockets, mountains, high buildings, etc.). Of course, this would not be possible if it were dark or foggy. But we here take for granted that you can see the surrounding and its objects.

The process of estimating one's present position based on various tools - we did not mention all the other tools which help to determine one's position - is called navigation.

Navigation is not only used in the real world but also in virtual environment. The Internet for example is full of hypertext and other multimedia applications. You can navigate through them like in real world but you cannot use the same tools as in real space to keep your orientation because in virtual space we have fewer sensors at hand to find our way.
In this virtual environment you can also have the feeling of being lost, because the web sites consist always of more than one object and it is not always easy to keep the orientation.

This lesson will deal with navigation in general and particularly with navigation for multimedia applications. The question how to avoid the "lost in hyperspace" feeling is one of the main part of this lesson. Of course, we do not only talk about the navigation of Internet applications, but also about the navigation in interactive 2D maps.