---
title: "History and Undo"
description: "Undo and redo while editing, and the history of every saved state of an image in LumiScan Annotation Web: compare a version with the editor and restore it."
product: "LumiScan Annotation Web"
component: "lumiscan-annotation-web"
version: "2.4.1"
display_version: "2.4.1.2"
latest_version: true
language: "en"
url: "https://docs.hdvisionsystems.com/en/lumiscan-annotation-web/history-and-undo.html"
---

# History and Undo – LumiScan Annotation Web

## Undo and redo

While you edit an image, every box change is a step: `Ctrl+Z` undoes it, `Ctrl+Shift+Z` or `Ctrl+Y` redoes it, as do the buttons ↶ and ↷ in the toolbar. Holding an arrow key is one step.

## History

The **History** panel (on the right, at the bottom, click to open) lists every saved state of the open image, also from earlier days, with the time, the user and what happened: saved, decided in review, annotators agreed, restored, or changed outside the web app.

![History panel open: an older version of part_003.png is shown in pink over the image, with numbered markers where it differs from the boxes in the editor](https://docs.hdvisionsystems.com/en/lumiscan-annotation-web/_images/screens/history.jpg)

- Click a version to see it in **pink** over the image. Numbered markers show where it differs from the boxes in the editor.
- **Older** and **Newer** (or the keys `,` and `.`) step through the versions; **Close** hides it again.
- **Restore** puts the version into the editor as unsaved changes. Saving adds a new version; the history is never rewritten.

![History panel: the selected version from anna, compared with the editor 3 only in the version and 6 different, buttons Older, Newer, Close and Restore; below the list of versions](https://docs.hdvisionsystems.com/en/lumiscan-annotation-web/_images/screens/history-panel.png)

Changes made with the desktop tool on the same folder are kept as versions too, with the user from `<image>.json`. The history keeps the exact text of each CSV file, so restoring writes an earlier state back byte for byte.

With several annotators per image, annotators see the history of their own version only. Reviewers choose under **Show** whether they see the reference or one annotator’s history.