Trilium supports seamless versioning of notes by storing snapshots ("revisions") of notes at regular intervals.
Time interval of taking note snapshot is configurable in the Options -> Other dialog. This provides a tradeoff between more revisions and more data to store.
To turn off note versioning for a particular note (or subtree), add disableVersioning
label to the note.
Note revisions can be accessed through the button on the right of ribbon toolbar.