[//]: # (title: Glossary)

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See also [Oracle's Java Technology Glossary](https://www.oracle.com/java/technologies/glossary.html).

## A

Abstract Syntax Tree _(AST)_
: The [Abstract Syntax Tree](implementing_parser_and_psi.md) represents the structure of source input files.
&rarr; _Program Structure Interface_

Annotator
: Provides [semantic highlighting](syntax_highlighting_and_error_highlighting.md) based on underlying &rarr; _Program Structure Interface_ elements.
&rarr; _Inspection_

## D

Document Object Model _(DOM)_
: [DOM API](xml_dom_api.md) abstracts working with XML files based on a custom semantic model.

## E

Event Dispatch Thread _(EDT)_
: The [Event Dispatch Thread](https://docs.oracle.com/javase/tutorial/uiswing/concurrency/dispatch.html) handles all Swing events. See also [General Threading Rules](general_threading_rules.md).

Extension Point _(EP)_
: Most functionality is provided by [Using Extension Points](plugin_extensions.md) provided by the platform or plugins. Plugins can also [define their own](plugin_extension_points.md) to allow extensibility.

External System _(ES)_
: [External System](external_system_integration.md) allows integrating external project management systems.

## F

File Based Index _(FBI)_
: [File Based Index](file_based_indexes.md) allows storing key-value information based on the project's files.

## I

Inspection
: Supports configurable [semantic highlighting](code_inspections_and_intentions.md).
&rarr; _Annotator_

Intention
: Provides an [automated fix](code_inspections_and_intentions.md) for commonly encountered code problems.

## L

Local History _(LVCS)_
: A builtin &rarr; _Version Control System_ tracking all changes in the project [locally](https://www.jetbrains.com/help/idea/local-history.html).

## J

JetBrains Project System _(JPS)_
: Represents the project model in [External Build](external_builder_api.md#accessing-project-model-and-configuration-from-external-build) process.

JetBrains Runtime _(JBR)_
: The [JetBrains Runtime](ide_development_instance.md#using-a-jetbrains-runtime-for-the-development-instance) is the default bundled runtime for all IntelliJ Platform-based IDEs by JetBrains.

## P

Program Structure Interface _(PSI)_
: The [Program Structure Interface](psi.md) represents a syntactic and semantic code model of the source input files. &rarr; _Abstract Syntax Tree_ &rarr; _Stubs_

## R

Read Action
: Allows accessing code-related data structures for reading purposes. See also [General Threading Rules](general_threading_rules.md).
&rarr; _Write Action_

Run Configuration _(RC)_
: A [Run Configuration](basic_run_configurations.md) allows running external processes from within the IDE.

## S

Stubs
: A subset of a &rarr; _Program Structure Interface_ tree in a binary serialized compact format, see [Stub Indexes](stub_indexes.md).

## U

Unified Abstract Syntax Tree _UAST_
: An [abstraction layer](uast.md) on the &rarr; _Program Structure Interface_ of different JVM languages.

## V

Version Control System _(VCS)_
: The API for [Version Control System](vcs_integration_for_plugins.md) allows accessing builtin as well as adding custom implementations.

Virtual File _(VF)_
: A [Virtual File](virtual_file.md) represents a file in a &rarr; _Virtual File System_.

Virtual File System _(VFS)_
: A [Virtual File System](virtual_file_system.md) provides a unified API for working with files represented as &rarr; _Virtual File_.

## W

Write Action
: Allows accessing code-related data structures for writing purposes. See also [General Threading Rules](general_threading_rules.md).
&rarr; _Read Action_