ArcGIS Online is the ESRI online mapping platform. Affiliates can request a personal account through the Columbia Institutional subscription through the CIESIN GIS service center (under "request software authorization"). ArcGIS Online accounts can be used for data storage and sharing, web mapping and some spatial analysis. Accounts may be necessary for use of other ESRI platforms including ArcGIS Pro and StoryMaps.
ArcGIS StoryMaps is ESRI's platform for creating interactive, map-based, multi-media, narrative "scrollytelling" web projects.
CARTO is a "platform as a service" that offers a limited free account. Users can store data, create interactive web maps and access spatial analysis tools. Mapbox is a similar platform that likewise offers a limited free account.
The following is a partial list of tile servers and other basemap services that can be used for web mapping projects for limited free use.
Many basemap services are based on OpenStreetMap data. A partial list of these can be found at this OSM Wiki list of tile servers. OpenMapTiles provides tools to allow users to create their own vector map tiles from OpenStreetMap data for hosting, self-hosting, or offline use.
We also reccommend this list of over 100 services used in the Leaflet-providers plugin.
Stamen Maps provides some popular map styles from OSM data.
Likewise there are a number of ArcGIS Online Basemaps available for use.
Leaflet is a lightweight open-source library for creating interactive maps in the browser using XYZ tile servers and/or WMS services. Native support for data in GeoJSON format.
MapBox GL JS is the Mapbox library for creating browser based interactive maps from vector tiles.
OpenLayers is an open source library for creating interactive tile maps in the browser. Can pull tiles from available XYZ sources, also compatible with vector tiles. Supports vector data in GeoJSON, KML, GML, WKT and others. d3-geo-projection is a plugin that provides extended geographic projections.
D3 Data-Driven Documents (D3) is a popular library for producing vector based data visualizations. While not made specifically for cartography, D3 has robust mapping capabilities and projection support. Works with GeoJSON and KML.
Kartograph is a lightweight framework for SVG based maps without referencing other map servers. Meant to be simple and "created with the needs of designers and data journalists in mind"
CARTO.js is a library for working with CARTO APIs