OpenOffice.org (OO.o or OOo) is a free cross-platform office application suite available for a number of different computer operating systems. It supports the ISO standard OpenDocument Format (ODF) for data interchange as its default file format, as well as Microsoft Office formats among others.
OpenOffice.org was originally derived from StarOffice, an office suite developed by StarDivision and acquired by Sun Microsystems in August 1999. The source code of the suite was released in July 2000 with the aim of reducing the dominant market share of Microsoft Office by providing a free, open and high-quality alternative; later versions of StarOffice are based upon OpenOffice.org with additional proprietary components.
The project and software are informally referred to as OpenOffice, but this term is a trademark held by another party, requiring the project to adopt OpenOffice.org as its formal name. In version 2011 its replaced by LibreOffice:
LibreOffice (pronounced /ˌliː.brəˈɒ.fɪs/) is a free software office suite developed by The Document Foundation as a fork of OpenOffice.org, that is compatible with other major office suites and available on a variety of platforms. Its developers' goal is to produce a vendor-independent office suite with ODF support and without any copyright assignment requirements. The name is a hybrid word with the first part Libre, which means free (as in freedom) in both Spanish and French, and the English word Office. The Document Foundation aims to release new major versions of LibreOffice once every six months, and to eventually align with the March / September schedule of the wider Free Software ecosystem.