A cross-platform browser-based professional and totally free office suite with all the right goodies you could ever want...
It is not cloud-based and is completely server-less. This means it can be run online or offline without any problems. This web-based office suite is also the first in the world to be able to run as a Progressive Web Application on any platform and mobile device.
It is most capable to run on a desktop computer or tablet, whether it be Windows, Linux, iOS, Android, or ChromeOS.
It also has no need for Account registration or logins. It is open and completely free.