This glossary is in the process of being updated and has been compiled from numerous other sources including the OpenStreetMap Wiki site and a guide written by Will Skora. Feel free to help us update it by reviewing for how to contribute to the site. Reviewed 2015-07-18

To easily search this Glossary, use the search feature within your browser, by holding down the control key and whilst doing so press the f key (usually described as Ctrl+f)

3W : Who, What, Where; Who does What, Where?

AAR : After Action Review; A group activity to evaluate an exercise or activity to learn and improve.

Activation (HOT term) : Sometimes referred to as a crisis, disaster, or emergency response and generally characterized by a specific event and/or anticipated humanitarian impact with a relatively shorter time-frame associated with the response and recovery phases of the disaster cycle than a longer-term Humanitarian Project.

Activator(s) : HOT volunteers who have completed training and are endorsed by an existing activator to perform roles during events.

AOI : Area of Interest ; defined by activation coordinators in consultation with humanitarian partners, field teams and HOT community in wake of a disaster.

Changeset: A group of changes that you made to OSM data. Once uploaded to OSM, your edits are instantly available to others if they download them. They may take a few minutes or several hours to appear on the map.

COD : Common Operational Database ; Comprises the geographical data for multiple humanitarian activations. These are mainly: transportation network (roads, bridges/fords, ports etc.), populated places (settlements), administrative boundaries, hydrology (rivers and other bodies of water) and hypsography (elevations/contours). May include buildings as an indirect source of population statistics. Used by the United Nations Office for the Coordination of Humanitarian Affairs.

DHN : Digital Humanitarian Network ; organization which leverages digital network for humanitarian response.

Extract : OSM Data Overview A large chunk of OSM data for a specific area (like a state, country, or geographic area).

Field Papers: is a web-based tool for easily creating a printable map atlas for anywhere in the world that you can print and add notes to. See for more details.

FOD : Fundamental Operational Database ; data that is specific for to activation i.e. health facilities, schools, water facilities, flood extents, building damages, etc.

GDACS : Global Disaster Alert and Coordination System ; GDACS is a cooperation framework under the United Nations umbrella. It includes disaster managers and disaster information systems worldwide and aims at filling the information and coordination gap in the first phase after major disasters. GDACS provides real-time access to web‐based disaster information systems and related coordination tools.

iD editor - Web-based beginner-friendly OpenStreetMap editor designed by Mapbox.

IDP : Internally Displaced Person ; is a person that is forced to flee his or her home while continuing to remain within their country’s borders.

JOSM pronounced “Jaws-um”, OpenStreetMap editor written in Java.

Layer: A data source that’s displayed on a slippy map (often is thought of as a group of tiles stitched together).

NGO : Non Govermental Organisation / Agency ; primarily a not for profit compulsory group of citizens who are organized on a local, national or international level.

Node: A node is one of the core elements in the OpenStreetMap data model. It consists of a single point in space defined by its latitude, longitude and node id. Nodes can be used to define standalone point features, but are more often used to define the shape or “path” of a way.

OCHA : United Nations Office for the Coordination of Humanitarian Affairs ; OCHA is the part of the United Nations Secretariat responsible for bringing together humanitarian actors to ensure a coherent response to emergencies. OCHA also ensures there is a framework within which each actor can contribute to the overall response effort.

POC : Point of Contact ; person(s) to engage with for any enquiries, questions, coordination, etc.

Relation: one of the core data elements that consists of one or more tags and also an ordered list of one or more nodes, ways and/or relations as members which is used to define logical or geographic relationships between other elements. For examples go to the Types of Relations wiki page.

Render : to convert from data into an image. Rendered data is a map.

SBTF : Stand-By Task-Force ; an organization which coordinates digital volunteers into a responsive, trained, and prepared network ready to deploy in crises.

Slippy Map : What you see when you’re on ! Consists of a layer and a software library that controls interactive features like zooming & panning.

Stylesheet : In most instances, it means a text file that’s used to determine what features (which roads ?) are displayed, and how (what color should the road be ? Its width ? ) on a map.

Tag: Tags describe describe a point, line or polygons. Each tag contains a key and value (written in OSM as ‘key=value’). For example, highway=residential and name=Woodland Avenue. Initially mentioned in Learnosm within iD section A Point, line, or polygon usually have more than one tag on them. Sometimes choosing the right tag is confusing. Taginfo helps you by showing statistics about which tags are actually in the database, how many people use those tags, where they are used and so on. It also gets information about tags from the wiki and from other places.

TIGER : A data source from the US Census Bureau that was imported into OSM, in 2007. This is the source for most data in the USA in OSM.

Tile : a small image (256x256 pixels ) of rendered map data.

Way: an ordered list of nodes which normally also have at least one tag or is included within a Relation. A way can have between 2 and 2,000 nodes, although it’s possible that faulty ways with zero or a single node exist. A way can be open or closed.

  • A closed way closedwayimage is one whose last node on the way is also the first on that way. A closed way may be interpreted either as a closed polyline, or an area, or both.

  • An open way openwayimage is way describing a linear feature which does not share a first and last node. Many roads, streams and railway lines are open ways.

Note on OSM Editing Terms:

Many terms to describe map features in OSM are used in dialects of British English and spelled as such. Like neighbourhood.

Motorway: British English term for the most major highway, also considered as ‘freeway’

Pitch : used to describe a playing field. Including tennis courts, basketball courts, baseball diamonds, or football fields.