How does GPS work?
The advantage of digital mapping
Digital maps can be updated
Apart from the fact that traditional maps are less convenient and less interactive and therefore less efficient than digital maps, one of the main reasons traditional paper maps are being superseded by digital maps, is that a paper map cannot be updated.
On average, 5% of roads are altered in some way every year. So with a paper map that’s only 2 years old, you have close to a 1 in 10 chance of being wrongly directed with each reading you take!
In fact, given the time-lag between getting the data for the maps and then drawing them up, getting them typeset, printed, distributed and so on; a new paper map is already out of date before the ink on it is dry.
The on-going challenge to digital mapmakers is to reduce the delay between a change occurring in the road system and its appearing in the map in your navigation system.
The leading digital map suppliers (there are several, of which TeleAtlas and Navteq are the largest) employ literally hundreds of people to meet this challenge and make your digital map as up-to-date and accurate as possible.
More than just directions..
Even the earliest maps enhanced their basic cartography with additional information they hoped would be of interest to their readers. So with medieval maps you often see written across areas on the edges that were as yet unexplored warnings like ‘Hic sunt dracones’ meaning: ‘Here be dragons”.
The huge range of information digital maps can provide (with traffic signs, prohibited manoeuvres, vehicle restrictions, post/zip codes, house number ranges, points of interest, tourist information, speed camera data, and much more) is just another example of how much more user-friendly they are than traditional maps.
So whereas even the best traditional maps simply show you where you are, and perhaps indicate road signage etc (as it was at the time of printing), digital maps take the information you get to another level altogether:
• With route calculation – the best route according to the driver’s criteria (speed, scenery, fuel-consumption, etc), distances, points of interest, and so on.
• With route guidance – real-time information, for example on traffic flow (and non-flow!) and safety cameras; and support, for example with negotiating complex intersections, preparing you in advance for turn warnings; and much more.