What's the difference between LibreOffice and OpenOffice?
LibreOffice is a fork of OpenOffice, or to be more correct, a new name of office productivity suite being developed by many folks at OpenOffice.org. The reason for this is that Oracle, which bought Sun Microsystems (erstwhile corporate sponsor of OpenOffice) in 2010, asserted control over the development of OpenOffice, which went against the grain of the developers. They thus bolted out and formed the Document Foundation, which is the home of LibreOffice.
The codebase of OpenOffice is imported into LibreOffice, which means at this point in time, they do not differ in functionality. But in time, people might see minor to major differences between the two, as each has its own community already.
It so happens that UP Manila's de facto Linux distribution is Ubuntu. And Ubuntu supports LibreOffice.