Source-code editors have features specifically designed to simplify and speed up typing of source code, such as syntax highlighting, indentation, autocomplete and brace matchingfunctionality. These editors also provide a convenient way to run a compiler, interpreter, debugger, or other program relevant for the software-development process. So, while many text editors like Notepad can be used to edit source code, if they don't enhance, automate or ease the editing of code, they are not source-code editors. Structure editors are a different form of source-code editor, where instead of editing raw text, one manipulates the code's structure, generally the abstract syntax tree. In this case features such as syntax highlighting, validation, and code formatting are easily and efficiently implemented from the concrete syntax tree or abstract syntax tree, but editing is often more rigid than free-form text. Structure editors also require extensive support for each language, and thus are harder to extend to new languages than text editors, where basic support only requires supporting syntax highlighting or indentation. For this reason, strict structure editors are not popular for source code editing, though some IDEs provide similar functionality. A source-code editor can check syntax while code is being entered and immediately warn of syntax problems. A few source-code editors compress source code, typically converting common keywords into single-byte tokens, removing unnecessary whitespace, and converting numbers to a binary form. Such tokenizing editors later uncompressthe source code when viewing it, possibly prettyprinting it with consistent capitalizing and spacing. A few source-code editors do both.
Notable examples
Atom
BBEdit
Brackets
Eclipse
Emacs
Gedit
NetBeans
Notepad++
SlickEdit
SubEthaEdit
Sublime Text
TextMate
UltraEdit
vi/Vim
Visual Studio Code
Controversy
Many source-code editors and IDEs have been involved in ongoing user arguments, sometimes referred to jovially as "holy wars" by the programming community. Notable examples include vi vs. Emacs and Eclipse vs. NetBeans. These arguments have formed a significant part of internet culture and they often start whenever either editor is mentioned anywhere.