Different kinds of web maps…

Maps can be digital, web-based, or physical. And, quite often, projects will incorporate more than one kind of map in their output. However, any map can be categorized into one of two main kinds of maps: reference maps and thematic maps.

Reference maps are useful to show the lay of the land, such as the geographic context surrounding your research location or area of interest. Reference maps can be as simple as a drop-pin location, or more complex with multiple data layers, labeling, and insets. Thematic maps, on the other hand, use visualization techniques such as color, size, shape, and density to convey further information about a dataset. Writes Statistics Canada: “A thematic map shows the spatial distribution of one or more specific data themes for standard geographic areas.” For example, a map showing the population of each neighborhood by a color gradient would be a thematic map, as it visualizes the spatial distribution of population within the geographic area of neighborhoods.

There is a case to be made that all maps are thematic, as the definition of boundaries, borders, names, etc. is a political - and almost always contested - act. In other words, there are no neutral maps that “simply”, or impartially, represent an objective reality or truth. See Crampton and Krygier (2006) for a seminal introduction to critical cartography, or Wang and Liu (2022) for an overview of critical cartography and GIS through the last several decades. See also the classic by Denis Wood, The Power of Maps.

This workshop will focus on the anatomy and construction of reference web maps. However, examples of both reference web maps and thematic web maps are included below. Take a moment to familiarize yourself with what these may look like. What might be best for your project? The next section will introduce the different tools and platforms with which each of the following web maps were made.

Reference Web Maps

The most basic reference web map is a basemap, contained in a viewbox with controls and an attribution at the bottom. Explore the interactive capabilities of each of the following examples.

Some other reference web maps out there:

Falling Fruit is a foraging map, hosted by Google Maps. Everyday people can anonomysouly upload finds such as a lush patch of blackberries, alleyway lemonbalm, or a plum tree in a yard slated for demolition.
Native-land.ca shows Indigenous territories across Turtle Island and around the world. You can search First Nations by territories, languages, or treaties. The map can be overlaid upon a colonial, cartesian basemap. This web map is powered by Mapbox, with basemap tiles from Open Street Map.
Queering the map visualizes anonymized, user-submitted queer experiences around the world. While their basemap used to be Google Maps, it recently changed to Open Street Map. It’s unclear what library is powering the interactivity of this web map, but extended documentation is impressively available on Radical-data’s Github.

Thematic Web Maps

Thematic web maps visualize the results of some spatial analysis. With a bit of code, you can create choropleth, cluster, or proportional symbol web maps. Note, however, that the construction of thematic web maps often requires prior data processing and modification in software such as QGIS.

_{See below choropleth example as full-page map}

_{See below cluster map example as full-page map}

_{See below proportional symbol map example as full-page map}
Hover over the circles to learn the municipality population for Vancouver Island.

If you’re beginning to think web maps might not be for you, all reference and thematic maps can also be made statically. Check out the Research Common’s workshop on Telling Spatial Stories for guidance on determining the best output for your project goals.