The most popular free open source office suite, it includes a word processor, spreadsheet, presentation software etc. It’s very widely used by businesses, governments, organisations and individuals, and is available for Linux, Mac and Windows.

Fediverse address:
@libreoffice@fosstodon.org

There are also user groups on the Fediverse:

Fediverse address (in Spanish):
@LibreOfficeEs@mastodon.social

Fediverse address (in French):
@LaMouetteODF@framapiaf.org