An ODT file is a text document created with Writer, the Apache OpenOffice and StarOffice word processor. It contains different elements such as text, images, drawn objects, and styles. ODT files are formatted using the OASIS OpenDocument XML-based standard.
OpenDocument text files can be opened and edited with any OpenOffice-compatible program, including: NeoOffice (Mac), AbiWord (Mac & Windows), and KWord (Unix). They can also be imported into Google Docs, Google's Web-based word processor and spreadsheet application.
NOTE: Apache OpenOffice was formerly known as OpenOffice.org.