# Changing Text

Changing Text: Find and Replace in a Stream: sed.

Updated: November 10, 2026

1. [Find and Replace in a Stream: sed](https://www.ask-codey.com/lessons/bash-sed) (Journeyman): sed changes text as it flows past, replacing words with s/old/new/g and deleting lines with d, and sed -i.bak changes the files themselves while keeping a backup of each one.

Source: https://www.ask-codey.com/courses/bash-in-depth/topics/bash-changing-text