Open Office

OpenOffice.org is both a product and an open-source project. Both have been in existence since October 13th, 2000. OpenOffice.org 1.0, the product, was released on April 30th, 2002.
OpenOffice.org's mission statement was drafted by the community:

To create, as a community, the leading international office suite that will run on all major platforms and provide access to all functionality and data through open-component based APIs and an XML-based file format.

The OpenOffice.org project is primarily sponsored by Oracle, which is the primary contributor of code to the project. Our other corporate contributors include RedFlag CH2000 (RedOffice.com), and IBM, to name but two. Additionally over 500,000 people--unaffiliated individuals, business and government employees, and students from nearly every curve of the globe--have joined the project with the aim of creating the best possible office suite that all can use. Their work as a community is both invaluable and practical: people use what the community does. This is the essence of an open source community.
The remainder of this page summarizes the project and suggests how you can contribute to it.

Official site : http://www.openoffice.org/
Download Link : Click Here !