OpenLayers
OpenLayers makes it easy to put a dynamic map in any web page. It can display map tiles and markers loaded from any source. MetaCarta developed the initial version of OpenLayers and gave it to the public to further the use of geographic information of all kinds. OpenLayers is completely free, Open Source JavaScript, released under a BSD-style License.
OpenLayers is developed and supported by a number of organizations around the world. We are also looking for sponsors to help support the community. If you are in a position where you want to support the development of OpenLayers, but do not have development resources to share, you may be interested in supporting through our sponsorship program.
OpenLayers is a pure JavaScript library for displaying map data in most modern web browsers, with no server-side dependencies. OpenLayers implements a (still-developing) JavaScript API for building rich web-based geographic applications, similar to the Google Maps and MSN Virtual Earth APIs, with one important difference -- OpenLayers is Free Software, developed for and by the Open Source software community.
OpenLayers is a project of the Open Source Geospatial Foundation.
Furthermore, OpenLayers implements industry-standard methods for geographic data access, such as the OpenGIS Consortium's Web Mapping Service (WMS) and Web Feature Service (WFS) protocols. Under the hood, OpenLayers is written in object-oriented JavaScript, using components from Prototype.js and the Rico library. The OpenLayers code base already has hundreds of unit tests, via the Test.AnotherWay framework.
As a framework, OpenLayers is intended to separate map tools from map data so that all the tools can operate on all the data sources. This separation breaks the proprietary silos that earlier GIS revolutions have taught civilization to avoid. The mapping revolution on the public Web should benefit from the experience of history.
Releases are made available on the downloads page. Additionally, if you wish to use OpenLayers in a web application, you can include http://www.openlayers.org/api/OpenLayers.js in your page, to always get the latest release.
The code is also available in our Subversion repository. Using Subversion, you can keep up to the absolute bleeding edge of the code. If you wish to report a bug in the API, and you are able to use Subversion, please see if the bug has been fixed in Subversion first: OpenLayers is under rapid development, so things change quickly.
If you don't have Subversion or don't want to download the code, you can still try some live examples on openlayers.org. If you're familiar with JavaScript, try viewing the source of the examples to get an idea how the OpenLayers library is used.
OpenLayers is still undergoing rapid development, so expect a lot to change in the next few weeks and months. We need your support! Please check the wiki for the very latest updates and documentation, and thank you for taking an interest.