# Notes

Note is a central entity in Trilium. Main attributes of note are title and content.

### Note types

- text note - this is default note type which allows you to put rich text, images etc.
- code note - some kind of formal code, typically programming language (e.g. JavaScript) or data structure (e.g. JSON)
- image note - represents single image
- file note - represents uploaded file (e.g. docx MS Word document).
- render HTML note - this works as an output screen of attached scripts
- saved search note - contains saved search query and dynamically displays result of the search as its sub-notes
- relation map note - visualizes notes and their relations
- book note - displays its children notes, useful for reading many short notes
- mermaid - create diagrams and flowcharts using mermaid.js ↗
- canvas note - allows hand drawn notes and basic diagraming on an infinite canvas using excalidraw ↗

In Trilium there's no specific "folder" note type. Any note can have children and thus be a folder.

### Root note

There's one special note called "root note" which is root of the note tree. All other notes are placed below it in the structure.

### Tree structure

Importantly, note itself doesn't carry information on its placement in note tree. See cloning for details.

Tree structure of notes can resemble file system - but compared to that notes in Trilium can act as both file and directory - meaning that note can both have its own content and have children. "Leaf note" is a note which doesn't have any children.

### Deleting / undeleting notes

When you delete a note in Trilium, it is actually only marked for deletion (soft-delete) - the actual content, title, attributes etc. are not deleted, only hidden.

Within (by default) 7 days, it is possible to undelete these soft-deleted notes - open Recent Changes dialog, and you will see a list of all modified notes including the deleted ones. Notes available for undeletion have a link to do so. This is kind of "trash can" functionality known from e.g. Windows.

Clicking an undelete will recover the note, it's content and attributes - note should be just as before being deleted. This action will also undelete note's children which have been deleted in the same action.

To be able to undelete a note, it is necessary that deleted note's parent must be undeleted (otherwise there's no place where we can undelete it to). This might become a problem when you delete more notes in succession - the solution is then undelete in the reverse order of your deletion.

After the 7 days (configurable) the notes will be "erased" - their title, content, revisions and attributes will be erased, and it will not be possible anymore to recover them (unless you restore backup).

## See also

- Read-only note