IDLE is a development environment for the Python programming language.[1] It enjoys a clean and simple user interface yet provides virtually all basic tools necessary for efficient programming. Entirely written in Python, it works on multiple platforms including Unix, Windows and Macintosh. Since the release 1.5.2, it is installed automatically with the standard Python bundle.[2]
By default, at start up the interactive shell window appears. It should not, however, be confused with the command line prompt, another standard part of the Python installation bundle. At the shell level, IDLE provides greater functionality, including previous command search/recall and syntax highlighting.
Basic tool available with IDLE is a Python-compatible powerful text editor. This means not only smart indentation adapted to the python syntax requirements but also comprehensive search functions, auto-completion feature and language tips while typing. However, the editor neither allows the incremental search nor marks different indentation levels by vertical lines -- these features are often proposed by "external" Python-compatible text editors.
IDLE starts execution of Python code in a separate process and permits to break it in virtually any circumstances. Furthermore, it incorporates a debugger that features breakpoints, step-by-step control and full access to the stack. However it is noted in the basic description of IDLE[3] that with the ability to quickly add and test new portions of code within the interactive environment, the user may find the symbolic debugger of less use than in other languages. On notes also that at present it is not possible to pass the command line parameters to a script run from IDLE. Inserting a line of code that simulates command line invocation by setting up the sys.argv list is proposed instead.
User interface is customizable: essential options include font, colours for syntax-highlighting, shortkeys and startup defaults.