---
title: Implementing Undo - Computerphile
link: https://www.youtube.com/watch?v=S6PqsZ65Mg4
source: youtube-com-computerphile
published: 2026-09-30T13:00:36Z
updated: 2026-09-30T13:06:04Z
first_seen: 2026-09-30T15:55:26.614342265Z
authors:
- Computerphile
summary: |-
  We use undo daily, but have you thought about what goes into making a functional undo in a program? Dr Steve Bagley takes us through some of the things we need to think about if we're implementing it ourselves!

  Computerphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://jane-st.co/computerphile

  This video was filmed and edited by Sean Riley.

  Computerphile is a sister project to Brady Haran's Numberphile. More at https://www.bradyharanblog.com
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---

We use undo daily, but have you thought about what goes into making a functional undo in a program? Dr Steve Bagley takes us through some of the things we need to think about if we're implementing it ourselves!

Computerphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: https://jane-st.co/computerphile

This video was filmed and edited by Sean Riley.

Computerphile is a sister project to Brady Haran's Numberphile. More at https://www.bradyharanblog.com