A text editor is a type of software application used for editing plain text files. It provides a user-friendly interface for creating and modifying text, making it essential for programmers, writers, and anyone who works with text data. Popular examples include Notepad, Sublime Text, and Visual Studio Code. Text editors can range from simple applications with basic features to advanced tools that support syntax highlighting, code completion, and version control. They are crucial in software development, allowing developers to write and edit code efficiently while providing features that enhance productivity and collaboration.