glossary

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 CONTRIBUTING.md for how to contribute to the site.

Activation - 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.

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.

Extract: 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 http://fieldpapers.org/ for more details.

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

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).

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.

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.

Slippy Map: What you see when you're on osm.org! 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. 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 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 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 - we considered as 'freeway' motorway_link - on/off ramps

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