Editing Google Maps (section)

== Implementation ==
[[File:Google Maps and Street View redesigned screenshot.png|thumb|right|A split-view screenshot of Google Maps. In the bottom half ''Street Maps'' is shown, while in the top half ''Street View'' is shown. A user can zoom in and out of either of them independently of the zoom level of each.]]
As the user drags the map, the grid squares are downloaded from the server and inserted into the page. When a user searches for a business, the results are downloaded in the background for insertion into the side panel and map; the page is not reloaded. A hidden [[HTML element#Frames|iframe]] with form submission is used because it preserves browser history. Like many other Google web applications, Google Maps uses [[JavaScript]] extensively.<ref>{{cite news |url=http://www.techgau.org/2012/06/google-revises-their-map-adds-offline.html |title=Google Revises Their Map, Adds Offline Version and 3D Imaging |publisher=TechGau.org |author=Gautham, A. S. |access-date=June 9, 2012 |url-status=live |archive-url=https://web.archive.org/web/20120613173216/http://www.techgau.org/2012/06/google-revises-their-map-adds-offline.html |archive-date=June 13, 2012 }}</ref> The site also uses protocol buffers for data transfer rather than [[JSON]], for performance reasons.

The version of [[Google Street View]] for classic Google Maps required [[Adobe Flash]].<ref>{{cite news|url=https://www.theguardian.com/technology/2009/mar/20/google-street-view1|title=Where the streets all have Google's name|last=Arthur|first=Charles|date=March 20, 2009|access-date=April 27, 2017|archive-url=https://web.archive.org/web/20170305025955/https://www.theguardian.com/technology/2009/mar/20/google-street-view1|archive-date=March 5, 2017|url-status=live|work=[[The Guardian]]}}</ref> In October 2011, Google announced MapsGL, a [[WebGL]] version of Maps with better renderings and smoother transitions.<ref>{{cite web|url=http://googleblog.blogspot.com/2011/10/step-inside-map-with-google-mapsgl.html|title=Step inside the map with Google MapsGL |date= October 13, 2011 |first1=Brian |last1=McClendon |publisher=Official Google Blog|archive-url=https://web.archive.org/web/20120410055542/http://googleblog.blogspot.com/2011/10/step-inside-map-with-google-mapsgl.html|archive-date=April 10, 2012|url-status=live|access-date=April 25, 2012}}</ref> Indoor maps use JPG, .PNG, .PDF, .BMP, or .GIF, for [[floor plan]]s.<ref>{{cite web|url=https://support.google.com/maps/answer/2803784?co=GENIE.Platform=Desktop|title=Use indoor maps to view floor plans – Computer |website=Google Maps Help|archive-url=https://web.archive.org/web/20170227062834/https://support.google.com/maps/answer/2803784?co=GENIE.Platform=Desktop|archive-date=February 27, 2017|url-status=live}}</ref>

Users who are logged into a [[Google Account]] can save locations so that they are overlaid on the map with various colored "pins" whenever they browse the application. These "Saved places" can be organized into default groups or user named groups and shared with other users. "Starred places" is one default group example. It previously automatically created a record within the now-discontinued product [[Google Bookmarks]].

=== Map data and imagery ===
{{See also|List of satellite map images with missing or unclear data}}The Google Maps terms and conditions<ref>{{cite web|url=https://maps.google.com/help/terms_maps.html|title=Google Maps/Google Earth Additional Terms of Service |publisher=Google Maps|archive-url=https://web.archive.org/web/20100208034157/http://maps.google.com/help/terms_maps.html|archive-date=February 8, 2010|url-status=live|access-date=January 13, 2010}}</ref> state that usage of material from Google Maps is regulated by Google Terms of Service<ref>{{cite web|url=https://www.google.com/intl/en/policies/terms/|title=Google Terms of Service |website=Google |archive-url=https://web.archive.org/web/20120125031300/http://www.google.com/intl/en/policies/terms/|archive-date=January 25, 2012|url-status=live|access-date=January 13, 2010}}</ref> and some additional restrictions. Google has either purchased local map data from established companies, or has entered into lease agreements to use copyrighted map data.<ref>{{Cite web|url=https://www.google.com/help/legalnotices_maps/|title=Legal Notices for Google Maps/Google Earth and Google Maps/Google Earth APIs |website=Google |access-date=October 3, 2019|archive-date=January 19, 2021|archive-url=https://web.archive.org/web/20210119143234/https://www.google.com/help/legalnotices_maps/|url-status=live}}</ref> The owner of the copyright is listed at the bottom of zoomed maps. For example, street maps in Japan are leased from [[Zenrin]]. Street maps in China are leased from [[AutoNavi]].<ref name="Lee-2012">{{cite web|url=https://www.bloomberg.com/news/2012-07-05/apple-shares-google-china-map-partner-in-win-for-autonavi.html |url-access=subscription |title=Apple Shares Google China Map Partner in Win for Autonavi|last=Lee|first=Mark|website=[[Bloomberg News]]|date=July 5, 2012|archive-url=https://web.archive.org/web/20141018152101/http://www.bloomberg.com/news/2012-07-05/apple-shares-google-china-map-partner-in-win-for-autonavi.html|archive-date=October 18, 2014|url-status=live}}</ref> Russian street maps are leased from Geocentre Consulting and [[Tele Atlas]]. Data for [[North Korea]] is sourced from the companion project [[Google Map Maker]].

Street map overlays, in some areas, may not match up precisely with the corresponding satellite images. The street data may be entirely erroneous, or simply out of date: "The biggest challenge is the currency of data, the authenticity of data," said Google Earth representative [[Brian McClendon]]. As a result, in March 2008 Google added a feature to edit the locations of houses and businesses.<ref>{{cite web|url=https://maps.google.com/help/maps/edit/|title=Improve information in Google Maps for the world to see|publisher=Google Maps|archive-url=https://web.archive.org/web/20071212195236/https://maps.google.com/help/maps/edit/|archive-date=December 12, 2007|url-status=dead}}</ref><ref>{{cite web|url=http://google-latlong.blogspot.com/2008/03/its-your-world-map-it.html|title=Google LatLong: It's your world. Map it|last=Balakrishnan|first=Ramesh|date=March 18, 2008|publisher=Google-latlong.blogspot.com|archive-url=https://web.archive.org/web/20091230065026/http://google-latlong.blogspot.com/2008/03/its-your-world-map-it.html|archive-date=December 30, 2009|url-status=live|access-date=January 13, 2010}}</ref>

Restrictions have been placed on Google Maps through the apparent censoring of locations deemed potential security threats. In some cases the area of redaction is for specific buildings, but in other cases, such as Washington, D.C.,<ref>{{cite news|url=https://www.washingtonpost.com/wp-dyn/content/article/2007/07/21/AR2007072101296.html|title=Google's View of D.C. Melds New and Sharp, Old and Fuzzy|last=Johnson|first=Jenna|date=July 22, 2007|access-date=May 3, 2010|archive-url=https://web.archive.org/web/20110213102542/http://www.washingtonpost.com/wp-dyn/content/article/2007/07/21/AR2007072101296.html|archive-date=February 13, 2011|url-status=live|newspaper=[[The Washington Post]]}}</ref> the restriction is to use outdated imagery.

=== Google Maps API ===
Google Maps API, now called Google Maps Platform, hosts about 17 different [[API]]s, which are themed under the following categories: Maps, Places and Routes.<ref>{{Cite web|url=https://developers.google.com/maps/documentation|title=Google Maps Platform Documentation|website=Google for Developers |language=en-US|access-date=2020-06-23|archive-date=January 28, 2021|archive-url=https://web.archive.org/web/20210128011427/https://developers.google.com/maps/documentation|url-status=live}}</ref>

After the success of reverse-engineered mashups such as chicagocrime.org and housingmaps.com, Google launched the Google Maps API in June 2005<ref>{{cite web|url=http://googleblog.blogspot.com/2005/06/world-is-your-javascript-enabled_29.html|title= The world is your JavaScript-enabled oyster |website=Official Google Blog |date= June 29, 2005  |first1=Bret |last1=Taylor |archive-url=https://web.archive.org/web/20090930054454/http://googleblog.blogspot.com/2005/06/world-is-your-javascript-enabled_29.html|archive-date=September 30, 2009|url-status=live}}</ref> to allow developers to integrate Google Maps into their websites. It was a free service that did not require an [[API key]] until June 2018 (changes went into effect on July 16), when it was announced that an API key linked to a Google Cloud account with billing enabled would be required to access the API.<ref>{{Cite web|url=https://cloud.google.com/maps-platform/user-guide/|title=User Guide {{!}} Google Maps Platform |website=Google Cloud|language=en|access-date=2018-07-10|archive-date=November 12, 2020|archive-url=https://web.archive.org/web/20201112030654/https://cloud.google.com/maps-platform/user-guide|url-status=dead }}</ref> The API {{as of|2010|8|25|alt=currently}} does not contain ads, but Google states in their terms of use that they reserve the right to display ads in the future.<ref>{{cite web|url=https://developers.google.com/maps/terms?csw=1 |website=Google |title=Google Maps API – Terms of use|archive-url=https://web.archive.org/web/20131224113528/https://developers.google.com/maps/terms?csw=1|archive-date=December 24, 2013|url-status=live}}</ref>

By using the Google Maps [[Application programming interface|API]], it is possible to embed Google Maps into an external website, onto which site-specific data can be overlaid.<ref>{{cite web|url=http://syntaxxx.com/php-and-mysql-working-with-google-maps/|title=PHP and MySQL: Working with Google Maps|first=Ian|last=Rose|publisher=Syntaxxx |date= February 12, 2014 |archive-url=https://web.archive.org/web/20141018175658/http://syntaxxx.com/php-and-mysql-working-with-google-maps/|archive-date=October 18, 2014|url-status=dead|access-date=October 13, 2014}}</ref> Although initially only a [[JavaScript]] API, the Maps API was expanded to include an API for [[Adobe Flash]] applications (but this has been deprecated), a service for retrieving static map images, and [[web service]]s for performing [[geocoding]], generating driving directions, and obtaining elevation profiles. Over 1,000,000<ref>{{cite web|url=http://googlegeodevelopers.blogspot.com/2013/05/a-fresh-new-look-for-maps-api-for-all.html |website=Google Maps Platform  |first1=Ken |last1=Hoetmer |title=A fresh new look for the Maps API, for all one million sites|date=May 15, 2013|archive-url=https://web.archive.org/web/20131128131730/http://googlegeodevelopers.blogspot.com/2013/05/a-fresh-new-look-for-maps-api-for-all.html|archive-date=November 28, 2013|url-status=live}}</ref> web sites use the Google Maps API, making it the most heavily used web application development API.<ref>{{cite web|url=http://www.programmableweb.com/apis|title=APIs Dashboard |publisher=ProgrammableWeb |archive-url=https://web.archive.org/web/20160430191115/http://www.programmableweb.com/apis|archive-date=April 30, 2016|url-status=dead |access-date=May 4, 2016}}</ref> In September 2011, Google announced it would deprecate the Google Maps API for Flash.<ref>{{cite web|url=http://googleblog.blogspot.com/2011/09/fall-spring-clean.html |website=Official Google Blog |title=A fall spring-clean|first=Alan|last=Eustace|date=September 2, 2011|archive-url=https://web.archive.org/web/20110907013015/http://googleblog.blogspot.com/2011/09/fall-spring-clean.html|archive-date=September 7, 2011|url-status=live|access-date=September 2, 2011}}</ref>

The Google Maps API was free for commercial use, provided that the site on which it is being used is publicly accessible and did not charge for access, and was not generating more than 25,000 map accesses a day.<ref>{{cite web|url=https://developers.google.com/maps/faq?csw=1#tos_commercial |website=Google for Developers |title=Google Maps API FAQ|archive-url=https://web.archive.org/web/20140116145315/https://developers.google.com/maps/faq?csw=1#tos_commercial|archive-date=January 16, 2014|url-status=live}}</ref><ref>{{cite web|url=https://developers.google.com/maps/faq?csw=1#usagelimits |website=Google for Developers |title=Google Maps API FAQ Usage Limits|archive-url=https://web.archive.org/web/20140116145315/https://developers.google.com/maps/faq?csw=1#usagelimits|archive-date=January 16, 2014|url-status=live}}</ref> Sites that did not meet these requirements could purchase the Google Maps API for Business.<ref>{{cite web|url=https://www.google.com/enterprise/mapsearth/|title=Google Maps for Business |website=Google |archive-url=https://web.archive.org/web/20131224021248/http://www.google.com/enterprise/mapsearth/|archive-date=December 24, 2013|url-status=dead }}</ref>

As of June 21, 2018, Google increased the prices of the Maps API and requires a billing profile.<ref>{{cite web |title=Introducing Google Maps Platform |url=https://cloud.google.com/blog/products/maps-platform/introducing-google-maps-platform |website=Google |access-date=14 September 2022 |date=2 May 2018 |archive-date=September 14, 2022 |archive-url=https://web.archive.org/web/20220914030637/https://cloud.google.com/blog/products/maps-platform/introducing-google-maps-platform |url-status=live }}</ref>

=== Google Maps in China ===
Due to [[restrictions on geographic data in China]], Google Maps must partner with a Chinese digital map provider in order to legally show Chinese map data. Since 2006, this partner has been [[AutoNavi]].<ref name="Lee-2012" />

Within China, the State Council mandates that all maps of China use the [[GCJ-02]] coordinate system, which is offset from the [[WGS-84]] system used in most of the world. google.''cn''/maps (formerly Google Ditu) uses the GCJ-02 system for both its street maps<ref>{{cite web|url=http://google.cn/maps/@31.2423,121.4914,20z|title=Google China street map uses GCJ-02 coordinates|author1=Monument to the People's Heroes|author-link1=Monument to the People's Heroes (Shanghai)|archive-url=https://web.archive.org/web/20170525200300/http://www.google.cn/maps/%4031.2423%2C121.4914%2C20z|archive-date=May 25, 2017|access-date=April 8, 2015}}</ref> and satellite imagery.<ref>{{cite web|url=http://google.cn/maps/@31.24228,121.49142,137m/data=!3m1!1e3|title=Google China satellite imagery uses GCJ-02 coordinates|author1=Monument to the People's Heroes|author-link1=Monument to the People's Heroes (Shanghai)|archive-url=https://web.archive.org/web/20170525200729/http://www.google.cn/maps/%4031.24228%2C121.49142%2C137m/data%3D%213m1%211e3|archive-date=May 25, 2017|access-date=April 8, 2015}}</ref> google.''com''/maps also uses GCJ-02 data for the street map, but uses WGS-84 coordinates for satellite imagery,<ref>{{cite web|url=https://www.google.com/maps/@31.2423,121.4914,267m/data=!3m1!1e3|title=Google.com satellite imagery uses WGS-84 coordinates|author1=Monument to the People's Heroes|author-link1=Monument to the People's Heroes (Shanghai)|archive-url=https://web.archive.org/web/20151118150131/https://www.google.com/maps/@31.2423,121.4914,267m/data=!3m1!1e3|archive-date=November 18, 2015|url-status=live|access-date=April 8, 2015}}</ref> causing the so-called [[restrictions on geographic data in China#GPS shift problem|China GPS shift problem]].

Frontier alignments also present some differences between google.''cn''/maps and google.''com''/maps. On the latter, sections of the Chinese border with India and Pakistan are shown with dotted lines, indicating areas or frontiers in dispute. However, google.''cn'' shows the Chinese frontier strictly according to Chinese claims with no dotted lines indicating the border with India and Pakistan. For example, the [[South Tibet]] region claimed by China but administered by India as a large part of [[Arunachal Pradesh]] is shown inside the Chinese frontier by google.''cn'', with Indian highways ending abruptly at the Chinese claim line. Google.''cn'' also shows Taiwan and the [[South China Sea Islands]] as part of China. Google Ditu's street map coverage of Taiwan no longer omits major state organs, such as the Presidential Palace, the [[Constitution of the Republic of China|five Yuans]], and the Supreme Court.<ref>{{cite web|url=https://www.google.com/streetview/understand/|title=Where We've Been & Where We're Headed Next|archive-url=https://web.archive.org/web/20170928204734/https://www.google.com/streetview/understand/|archive-date=September 28, 2017|url-status=live|access-date=January 2, 2018}}</ref>{{additional citation needed|date=April 2022}}

Google.''cn''/maps does not provide My Maps. On the other hand, while google.''cn'' displays virtually all text in Chinese, google.''com''/maps displays most text (user-selectable real text as well as those on map) in English.{{citation needed|date=April 2022}} This behavior of displaying English text is not consistent but intermittent – sometimes it is in English, sometimes it is in Chinese. The criteria for choosing which language is displayed are not known publicly.{{citation needed|date=April 2022}}