Nextcloud is a free and open source software that allows you to upload and storage files on a server (it could be a server of your own), and syncing them with different devices to which you can safely access from anywhere via internet. Some of the features it provides are: calendars, contacts and bookmarks synchronization, call/video conference, a basic project board, news feeder and more.
It is Disroot's core service and the main user interface we try to integrate with most of the apps we offer.
In the following chapters of this Cloud howto, we will learn about the interface, the basics of its operation and the main features of Nextcloud, as well as some basic actions on files and personal settings.