Google Maps

Screenshot of Google Maps showing a route from Toronto to Ottawa

Penang island and Province Wellesley on the mainland as seen on Google Maps [1]

Google Maps is the conventional name of a free, web map server application and technology provided by Google at http://maps.google.com and as part of Google Local. It offers draggable street map and satellite images for the whole world, as well as a route planner and business locator for the U.S., Canada, Japan, Hong Kong, China, the UK and Ireland (city centres only). On October 6, 2005, Google Maps was integrated into Google Local, though the core technology is still called Google Maps. A related product is Google Earth, a standalone Windows program that offers enhanced globe-viewing features.

Development

Google Maps was first announced on the Google Blog on February 8, 2005. It originally only supported users of Internet Explorer and Mozilla web browsers, but support for Opera and Safari was added on February 25, 2005. It was in beta for 6 months before becoming part of Google Local on October 6, 2005.

Like other Google web applications, a large amount of JavaScript was used to create Google Maps. As the user drags the map, the grid squares are downloaded from the server and displayed to the user. When a user searches for a business, the location is pin-pointed with a red pin, which is actually a transparent PNG placed over the map. The technique of providing greater user-interactivity by performing asynchronous network requests with Javascript and XML has recently become known as Ajax.

The GIS (map) data used in Google Maps are provided by TeleAtlas and NAVTEQ, while the high-resolution satellite imagery is largely provided by DigitalGlobe and its QuickBird satellite, with some imagery also from government sources.

Features

Google Maps features a draggable map that can be zoomed in to show detailed street information. The user can control the map with the mouse or the arrow keys to move to the desired location. To allow for quick movement, the "+" and "-" keys can be used to control the zoom level. Users may enter an address, intersection or general area to quickly find it on the map.

Search results can be restricted to a certain area, thanks to Google Local. For example, someone can enter a query such as "Waffles in Ottawa" to find restaurants serving waffles near the city. This can be used to find a wide variety of businesses, such as theatres, restaurants or hotels.

Like many other map services, Google Maps allows for the creation of driving directions. It gives the user a step by step list of how to get to their destination, along with an estimate of the time required to reach it and the distance between the two locations.

The "link to this page" link on each Google Maps map puts a long URL on the clipboard which contains the latitude and longitude. The latitude and longitude can be used as input to NASA World Wind or TerraServer-USA, which in some cases has higher resolution imagery, though Multimap.com tends to have better quality imagery as well.

In late April 2005, Google added a Ride Finder feature to its maps, in which a person could locate a cab or shuttle in a major city in real-time. The person would have to hit the Update Position bar to find the vehicle's new location.

As of January 2 2006, Google Maps features road maps for the United States, Puerto Rico, Canada, the United Kingdom, and Japan.

In mid July 2005, Google began Google Maps and Google Local services for Japan, including road maps.

In July 2005, in honor of the thirty-sixth anniversary of the Apollo Moon landing, Google Moon [3] was launched, which featured a draggable map and satellite imagery of the Moon's surface, created with data from NASA satellite imagery. A full zoom-in will humourously make the Moon's surface resemble cheese.

Satellite images

File:Stadium.PNG

Screenshot of Google Maps (satellite) showing Candlestick Park in San Francisco, CA

In early April 2005, an alternate view was activated to show satellite imagery of the area displayed. Google is also one of the first satellite imagery services that can overlay directions above the satellite image [4] (though Multimap.com has this previous to Google's adoption of the technology).

By June 2005, high-resolution (full-zoom) images were available for most urban areas in Canada and the United States -- including Hawaii and Alaska). Google has high-resolution pictures of parts of: France, Iceland, Italy, Iraq, Japan, the Bahamas, Bermuda, Kuwait, Mexico, the Netherlands, the United Kingdom, and many other countries.

Some areas are blurred for security reasons, including the United States Capitol, and the U.S. Naval Observatory, while the White House has been photoshopped. However, other well-known government installations are visible, such as Area 51 in the Nevada desert.

Since June 17, 2005 Google Maps is making more and more areas available in high resolution satellite imagery, including many areas and major cities of Europe.

Lower-resolution satellite imagery is available for the entire planet, except for the North and South Poles.

Not all the images are from satellites -- some urban images are aerial photographs taken from high-altitude aircraft.

Hybrid

On July 22, 2005, Google released a "hybrid" view of their Google Maps. This hybrid view combines the map and satellite view - essentially, overlaying the illustrated map and street names on the real-world satellite views. This makes it much easier to find routes, as it combines the benefits of both views. Together with this change, the satellite image data was converted from plate carrée to Mercator projection, which makes for a less distorted image in the temperate climes latitudes.

Popularity

With the introduction of an easily pannable and searchable mapping and satellite imagery tool, Google's mapping engine prompted a surge of interest in satellite imagery. Sites such as Google Sightseeing and Google Globetrotting were established which feature satellite images of interesting natural and man-made landmarks, including such novelties as "large type" writing visible in the imagery, as well as famous stadiums and unique earth formations.

Combined with photo sharing websites such as Flickr, a phenomenon called "memory maps" emerged. Using copies of the Keyhole satellite photos of their home towns or other favorite places, the users take advantage of image annotation features to provide personal histories and information regarding particular points of the area.

Extensibility and customization

File:Chicagocrime.jpg

Chicagocrime.org, developed by Adrian Holovaty, was among the first and most popular [2] Google Maps mashups.

The downloadable Google Earth allows customized use of Google Maps, with e.g. map images with town and street names overlaying satellite images.

As the Google Maps code is almost entirely JavaScript and XML, some end-users have reverse-engineered the tool and produced client-side scripts and server-side hooks which allow a user or website to introduce expanded or customized features into the Google Maps interface.

Using the core engine and the map/satellite images hosted by Google, such tools can introduce custom location icons, location coordinates and metadata, and even custom map image sources into the Google Maps interface. Some of the more well-known of these "Google Maps Hacks" include tools that display locations of Craigslist rental properties [5] and map Chicago crime data [6]. The script-insertion tool Greasemonkey provides a large number of client-side scripts to customize Google Maps data, and the mygmaps.com website provides an interface for easily adding your own set of locations and viewing them on Google Maps.

In late June 2005, Google released Google Maps API, exposing nearly the entire interface to customization. With a Google Maps API key, the API is free for use on any site that is free to the public. The introduction of the API has accelerated the development of new Google Maps-based applications, including a multi-player online game, Tripods.

Google's use of Google Maps

Google Local

Google integrates small-scale Google Maps views as part of its Local Search feature, which can find businesses of a certain category in a geographic area. Local Search is in turn available from Google Maps, based on the currently viewed area.

RideFinder

Google launched an experimental Google Maps-based tool called RideFinder, tapping into in-car GPS units for a selection of participating taxi and limousine services. The tool displays the current location of all supported vehicles of the participating services in major cities, including Chicago and San Francisco on a Google Maps street map.

Google Moon

On July 20, 2005, in honor of the 36th anniversary of the Apollo 11 moon landing, Google took public domain imagery from NASA of the Moon, and integrated it into the Google Maps interface. By default this tool, with a reduced set of features, also displayed the points of landing of all Apollo spacecraft to land on the moon. This tool also included an easter egg, displaying a Swiss cheese design at the highest zoom level. Google Moon, as it was called, was linked from a special commemorative version of the Google logo displayed at the top of the main Google search page for the duration of July 20 (UTC).

External links

Google Maps discussion websites

Examples of web tools employing Google Maps

Incidentlog.com, real-time and historic archive of police, fire, and 911 incidents for many major U.S. cities.
Cell Phone Reception and Tower Search, graphical cell phone reception and tower locator compiled from the FCC's antenna registration database.
Geobloggers.com, plots Geotagged Flickr photos on a map.
Google Maps Route Planner, clickable arbitrary-point driving direction generator.

Websites collecting Google Maps aerial views

List of images compiled by Wikipedia users
Google Sightseeing Showcase site of interesting views
Google Globetrotting Archival site of interesting views
Perljam's Links Another archival site