Apache OpenOffice 4.0.1

Apache OpenOffice (formally known as StarOffice and OpenOffice.org) is a fully functional, 100% free office software, similar to the MS Office and is the leading open-source office software suite  for word processing, spreadsheets, presentations, graphics, databases and more. If offers everything that you might need from similar product – text editor (OpenWriter), presentation package (OpenImpress), database server software (OpenBase), spreadsheet program (OpenCalc), and more. It can be downloaded and used completely free of charge for any purpose.

Product 
Compatible with other major office suites, OpenOffice is free to download, use, and distribute.

Writer
A word processor you can use for anything from writing a quick letter to producing an entire book. 

Calc
A powerful spreadsheet with all the tools you need to calculate, analyse, and present your data in numerical reports or sizzling graphics.

Impress
The fastest, most powerful way to create effective multimedia presentations. 

Draw
Lets you produce everything from simple diagrams to dynamic 3D illustrations. 

Base
Lets you manipulate databases seamlessly. Create and modify tables, forms, queries, and reports, all from within OpenOffice.org 

Math
Lets you create mathematical equations with a graphic user interface or by directly typing your formulas into the equation editor.