The Scrum Guide prescribes Events. In other words: not optional, but required. The reasoning behind the Events is that they will help a Scrum Team to have a regular heartbeat and also to avoid other meetings which are not a part of Scrum.
The Events are:
Scrum Events are always time-boxed. The length of a Sprint may not be changed. This helps the Scrum Team to stay focused and transparent. The other Events are equally time-boxed, but once the objective is accomplished for the particular Event, the Event can - and should be - ended.