Add glossary of terms to documentation

docs/glossary.rst

@@ -0,0 +1,68 @@
+Glossary
+========
+
+This glossary defines key terms used throughout Click's documentation.
+
+.. glossary::
+   :sorted:
+
+   Argument
+       A positional parameter passed to a command without a name prefix.
+       Arguments are identified by their position in the command line.
+       For example, in ``mycli command file.txt``, ``file.txt`` is an argument.
+
+   Callback
+       A function that is invoked when a parameter is processed. Callbacks can be
+       attached to options or arguments for custom validation or processing.
+       See :doc:`/parameters` for more information.
+
+   Command
+       A function decorated with ``@click.command()`` or ``@click.group()``
+       that can be invoked from the command line. Commands can accept options
+       and arguments.
+
+   Command Line Application
+       A Python program built with Click that provides a command line interface.
+       Command line applications use commands, options, and arguments to interact
+       with users through the terminal.
+
+   Command Line Interface (CLI)
+       A text-based interface for interacting with a program through commands,
+       options, and arguments. Click helps you build CLIs in Python.
+
+   Command Line Utility
+       A command line application designed to perform a specific task or set of
+       tasks. Command line utilities are often used for system administration,
+       file manipulation, or development workflows.
+
+   Context
+       An object that carries state between commands in a group hierarchy.
+       The context is created for each command invocation and can be accessed
+       via the ``@click.pass_context`` decorator.
+
+   Flag
+       A boolean option that doesn't take a value (e.g., ``--verbose`` or ``-v``).
+       Flags are either present (True) or absent (False).
+
+   Group
+       A command that contains other commands (subcommands). Created with
+       ``@click.group()``. Groups allow organizing commands hierarchically.
+
+   Multi-command
+       A command that groups multiple subcommands together. Groups and
+       multi-commands are similar concepts in Click.
+
+   Option
+       A named parameter passed to a command, typically with a dash prefix
+       (e.g., ``--name value`` or ``-n value``). Options can have values
+       or be used as flags.
+
+   Parameter
+       The general term for both options and arguments that can be passed
+       to a command. Parameters are defined using decorators like
+       ``@click.option()`` or ``@click.argument()``.
+
+   Terminal
+       A text-based interface for interacting with the operating system.
+       Also known as a command prompt, console, or shell. Command line
+       interfaces are used within a terminal to run commands and applications.

docs/index.rst

@@ -95,6 +95,7 @@ General Reference
 --------------------
 
 .. toctree::
+   glossary
    :maxdepth: 1
 
    parameters