CartoDB was officially launched in 2012 as a web mapping front end to a PostgreSQL + PostGIS back end database. The software was open source and could run on one's own hardware, but at the same time CartoDB offered an online subscription service wherein customers could upload datasets and make maps without having to touch the source code or configure anything themselves. In 2015 one of the best-known PostGIS masterminds, Paul Ramsey, joined CartoDB. In 2016 the company changed its name to CARTO and repositioned itself as a "location intelligence" tool rather than just a basic web mapping interface and online database. As such, it now also offers geodemographic analysis, routing, proximity, and address finding services.
Some of the services, you will note, are similar to those offered by the other SaaS offerings we are studying in this course: Mapbox and ArcGIS Online. This is inevitable because these companies have have found an eager market for the kinds of services they offer, and competition is a byproduct. In these course lessons, we have tried to focus the walkthroughs on some of the unique strengths of each platform or the technologies that they pioneered. One of CARTO's unique points is its variety of thematic mapping options and its appealing basemap and thematic styling options. The color schemes use the ColorBrewer ramps which were developed at Penn State and are based on scientific color theory. Cartographers using CARTO can aggregate point data to tesselated regions such as hexbins or their own boundary files that they upload. They can also make time series maps, rasterized heatmap-style density surfaces, proportional symbol maps, etc.
CARTO offers a "Builder" app for web-based design and an "Engine" piece consisting of APIs. CARTO services can perhaps be considered as either PaaS or SaaS. How can we distinguish between them? One way is to consider how they will be used. If the service is being used as a source and combined with others, then it is probably a platform service. If it is being consumed directly by the end user, then it's a software service. Along the same lines, if you access the service programmatically, it's more likely to be a platform service than if you access it with a GUI.
So, if we used CARTO as a source of web maps that we pass along to end users, then it's a software service. If we use CARTO as a "table in the cloud" then we would be using it as a platform. CARTO's provision of spatial data tables on the internet, along with both GUI and programmatic access for users and progammers, makes them a good example of a cloud GIS.