Glossary

This page defines the terms used in the docs and in API responses. Entries are alphabetical. Each one links to the page that explains it in full.

Agreement

How often we and Google Places identify the same place. See Accuracy.

Cell

An H3 cell or a geohash cell. Every dataset is stored per cell. See Query by coordinate, H3 cell or geohash.

Coverage

On the Data page, which countries and datasets the Data API has. On the Accuracy page, the share of places Google lists that we also have. See Data and Accuracy.

Cross-validated

A place that at least two independent sources list. Its source_count is 2 or more. See Source counts and min_sources.

data_version

The date of a country's public transport data, returned by GET /v1/pt/meta. The other datasets use last_refreshed. See Data updates.

Dataset

One of the six kinds of data in the Data API: places, public transport, roads, population and areas, green space and environment. Each has its own docs page. See What data you get.

Division

An administrative area from OpenStreetMap, such as a nation, a county or a district. GET /v1/divisions lists them. See Administrative areas.

ETag

A weak ETag header on GET /v1/pt/*, GET /v1/h3/transport/*, GET /v1/catalog and GET /v1/benchmark. It changes when the data does. No endpoint returns 304. See Caching and data dates.

Foursquare Open Places

One of the three places sources. Strongest for shops, restaurants and services. See Sources.

Geohash

A rectangular cell identified by a base32 string such as gcpvj0. The length of the string is its precision. Only the places dataset supports geohash. See Query by geohash.

H3 cell

A hexagonal cell from the H3 grid, identified by a hex string such as 89195da494bffff. Every dataset has resolution 9. See Query by H3 cell.

last_refreshed

The date of a country's data, returned by GET /v1/stats and GET /v1/catalog. See Data updates.

min_sources

A filter on every POI endpoint: the lowest source_count a place needs. See Source counts and min_sources.

Official register

A government or TravelTime dataset we use as the primary source for a category, such as the Care Quality Commission for hospitals, GPs and dentists in England. Places it confirms are verified. See Official registers.

OpenStreetMap (OSM)

One of the three places sources, and the source of administrative areas. Strongest for schools, parks, places of worship and transport. See Sources.

Overture

One of the three places sources, and the source of green space polygons. It combines several sources, including the other two. See Sources and Green space.

POI

A point of interest: a place with a name, a location and a category. See Points of interest.

Polygon

The shape of a green space on the ground. GET /v1/polygons lists polygons in an area, and GET /v1/h3/land-cover lists them per cell. See Green space.

Precision

The length of a geohash. The Data API has precision 6, about 1.2 km across, and 7, about 150 m across. See Query by geohash.

Resolution

The size of an H3 cell. Every dataset has resolution 9, with edges of about 175 m. Some also have 10, with edges of about 65 m. GET /v1/h3 lists the resolutions each dataset has. See Query by H3 cell.

Source count

source_count and the min_sources filter are defined in Source counts and min_sources.

Station and stop

A stop is one boarding point, such as a bus stop or a platform. A station is a group of stops that people think of as one place. Every transport endpoint returns stations. See Stations and stops.

TravelTime API

TravelTime's main product. It calculates travel times, routes and the H3 cells you can reach within a travel time. Send those cells to the Data API as cells. See Use with the TravelTime API.

Trip

One timetabled journey along a line. See Lines, trips and frequency.

/v1

The current API version prefix. Endpoints under /v1 are a stable contract. Breaking changes go to /v2. See Versioning.

Verified

verified is true when an official register confirms a place, or the place is a TravelTime public transport station. verified_by names what verified it. See How a place is verified.

Weekday morning

The am_peak band of a line's frequency object, one of five timetable bands. We recommend it when you need one figure per line. See Lines, trips and frequency.