"The free and very complete office automation solution"
Apache OpenOffice is a package with office tools very similar in features to Microsoft Office programs, which we all know, but made in open source and allows its free distribution.
In addition, this set of programs have nothing to envy to those of Microsoft Office since they are just as complete, effective and reliable as those of the paid version.
Your documents are compatible with all types of computers and you will be able to open documents made in Office without problems, in the same way that Microsoft Office users will be able to open documents created with this program.
The only drawback is that it doesn't have an email manager but that's certainly not a problem if you want to switch to Open Source and leave Microsoft.