LibreOffice

LibreOffice

Writer, Calc, Impress, Draw, Base, Math, Charts

Open source, free, downloads include a portable app.
Forked from Apache Open Office.
One key difference is that LibreOffice allows users to embed fonts into documents. If this is an important feature for you, then LbreOffice is it.

Apache OpenOffice

Apache OpenOffice

Excerpt from Apache Office Suite website:

• 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, analyze, 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 Apache OpenOffice.
• Math lets you create mathematical equations with a graphic user interface or by directly typing your formulas into the equation editor.

Free for private, commercial use.