Web Mapping Frequently Asked Questions

What are the choices of base maps?

Pretty much anything can be a basemap. But, commonly the choices are:

  • OSGB, both from their servers and your own.
  • Google and Bing
  • Openlayers and other open source maps
  • ESRI maps

What are the hosting options for web maps?

Both onsite and in the cloud. If you have a backend for editing map data, locally hosted would be a suitable choice.
The base maps do not have to be in the same location as the data layers. For example, if the maps came from OSGB, you could have the framework installed in the Amazon cloud, pulling in the layers from your own databases or whatever datasource it is.

Can we edit and save changes in web maps?

Yes you can. Even to the level that you could make a change to a layer, save the changes and users would see the changes immediately.

What about types of data on a map?

The list the data (layers) can come from is huge. But, a few examples could be, data.gov, Veolia, NHS hospitals and doctors, NCP parking information and car park locations, your own created data.

How does licencing and costs work?

There is no charge for the software (excludes basemaps), the cost is the consulting and installation then licensing on a yearly contract.

What is GIS?

GIS stands for Geographic Information Systems. A system designed to present spatial and geographic data. These systems often encompass ways to gather or collect data, like a satellite to gather, Geoserver to store the data, Arcgis to manipulate and edit, Arcgis to analyse and query the data and possibly a web map to present the data as information. The system often composes multiple parts, for example, Mapserver to store the data, ESRI Arcgis to edit and query the data and webmaps like Google Maps to view the results.

What are the UK map projections?

The CRS (coordinate reference system) ia EPSG: 27700 / OSGB 1936

What shape is the Earth and why is it difficult to map?

If the earth were a perfect sphere, mapping would be easier but not perfect (as maps are flat and 2D and the world is 3D). The actual shape of the earth is called an Oblate Spheroid. Bulging at the equator and flattened at the poles.
All the primary shapes like sphere, ellipes etc, have mathematical equations that cab create and set parameters for these. The earth is a shape that has no perfect mathematical equation to replicate so, the closest shape to the earth is an ellipsoid. The problem is now mapping a shape that isnt the shaoe of the earth, this is an issue. A common ellipsoid used as a reference ellipsoid in cartography is WGS84.

What are the types of map data?

Discrete: real world stuff like roads, houses, rivers, woodland
Continuous: area recordings like surface temparatures, elevations, flow etc

What is georeferencing?

Quite simply, if I had a photo of a field, associating that photo with coordinates to fix it at that real world position.