A tag is a keyword or label that categorizes your question with other, similar questions.

Scala is a general-purpose programming language principally targeting the Java Virtual Machine. Designed to express common programming patterns in a concise, elegant, and type-safe way, it fuses both imperative and functional programming styles. Its key features are: an advanced static type system with type inference; function types; pattern-matching; implicit parameters and conversions; operator overloading; full interoperability with Java; concurrency
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A function (also called a procedure, method, subroutine, or routine or macro) is a portion of code intended to carry out a single, specific task. Use this tag for questions which specifically involve creating or calling functions. For help implementing a function to perform a task, use [algorithm] or a task-specific tag instead. By creating function the logic can be isolated and can be called repeatedly.
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DO NOT USE. Use specific tags like [google-cloud-platform], [facebook], [amazon-web-services] instead or [api-design] where applicable. Questions asking to recommend or find an API are off-topic.
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Vue.js is an open-source, progressive JavaScript framework for building user interfaces that aims to be incrementally adoptable. Vue.js is mainly used for front-end development and requires an intermediate level of HTML and CSS. Vue.js questions are highly version specific and should always be tagged with [vuejs2] or [vuejs3] in addition to this tag.
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Bootstrap is a frontend framework designed to kick-start development of Web apps and sites. For questions related to a version of Bootstrap also use the specific version's tag from "twitter-bootstrap-2", "twitter-bootstrap-3", "bootstrap-4" and "bootstrap-5" tags.
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Selenium is a popular open-source tool for automating web browsers. When using this tag, also include other tags for the specific components you are using, e.g. selenium-webdriver for the language bindings, selenium-ide, selenium-grid, etc.
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For questions pertaining to the measurement or improvement of code and application efficiency.
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WinForms is the informal name given to Windows Forms, a GUI class library in the Microsoft .NET Framework and Mono. Questions in this tag should also be tagged with the target framework ([.net] or [mono]) and should ordinarily be tagged with a programming language tag.
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Loops are a type of control flow structure in programming in which a series of statements may be executed repeatedly until some condition is met.
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Python 2.7 is the last major version in the 2.x series, and is no longer maintained since January 1st 2020. Use the generic [python] tag on all Python questions. Do not add this tag simply to convey the version of Python you're using, unless the question concerns an issue specific to Python 2.7.
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MATLAB is a high-level language and interactive programming environment for numerical computation and visualization developed by MathWorks. Don’t use both the [matlab] and [octave] tags, unless the question is explicitly about the similarities or differences between the two. When using this tag, please mention the MATLAB release you're working with (e.g. R2017a).
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Hibernate is an object-relational mapping (ORM) library for the Java language enabling developers to utilize POJO-style domain models in their applications in ways extending well beyond Object/Relational Mapping.
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Express.js is a minimal and flexible Node.js web application framework providing a robust set of features for building web applications.
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SQLite is an open-source software library that implements a self-contained, serverless, zero-configuration, transactional SQL database engine. SQLite is the most widely deployed SQL database engine in the world.
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REST (Representational State Transfer) is a style of software architecture for distributed hypermedia systems such as the World Wide Web. It has increased in popularity relative to RPC architectures such as SOAP due to the intrinsic de-coupling of client from server that comes from having a uniform interface between heterogeneous systems.
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Use this tag (along with an appropriate programming-language tag) for programming questions relating to the Apache HTTP Server. Do not use this tag for questions about other Apache Foundation products. Note that server configuration questions are usually a better fit on https://serverfault.com
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The term 'shell' refers to a general class of text-based interactive command interpreters most often associated with the Unix & Linux operating systems. For questions about shell scripting, please use a more specific tag such as 'bash', 'powershell' or 'ksh'. Without a specific tag, a portable (POSIX-compliant) solution should be assumed, though using 'posix' in addition or 'sh' instead is preferable.
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Entity Framework is a LINQ-based object-database mapper for .NET. It supports change tracking, updates, and schema migrations for many databases. Please add a version-specific tag as well.
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Kotlin is a cross-platform, statically typed, general-purpose high-level programming language with type inference. This tag is often used alongside additional tags for the different targets (JVM, JavaScript, native, etc.) and libraries/frameworks (Android, Spring, etc.) used by Kotlin developers, if the question relates specifically to those topics.
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Dart is a class-based, statically(& strongly)-typed programming language for building web and mobile applications. Dart compiles to modern JavaScript to run in the browser and compiles to native code to run on mobile platforms like Android and iOS. Dart also runs on the command-line for scripting and server-side apps.
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Use for questions about using Android Studio, an official IDE by Google targeted at Android app development. Do NOT use for questions about programming for Android in general; instead, use the [android] tag.
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Comma-Separated Values or Character-Separated Values (CSV) is a common "flat file database" (or spreadsheet-style) format for storing tabular data in plain text, with fields separated by a special character (comma, tab, etc). Rows are typically denoted by newline characters. Use for any delimited file formats, including tab delimited (TSV)
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Apache Maven is a build automation and project management tool used primarily for Java projects. This tag is for questions that don't relate to a specific Maven version. Use the gradle tag instead for questions relating to Gradle.
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Language Integrated Query (LINQ) is a Microsoft .NET Framework component that adds native data querying capabilities to .NET languages. Please consider using more detailed tags when appropriate, for example [linq-to-sql], [linq-to-entities] / [entity-framework], or [plinq]
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Facebook Platform lets developers integrate their apps directly into the Facebook social networking service. Use this tag for questions which may arise when developing FOR Facebook. This tag is NOT for support questions about using the Facebook website or the official Facebook app. It is also NOT for questions of the “I want to implement a feature similar to what Facebook has” variety.
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Qt is a cross-platform application development framework widely used for the development of application software that can be run on various software and hardware platforms with little or no change in the underlying codebase, while having the power and speed of native applications. Qt is available with both commercial and open source licenses.
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A dictionary maps keys to values allowing efficient retrieval of values by keys. Use the [map-function] tag for mapping functions; use the [maps] tag for geography.
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Unit testing is a method by which individual units of source code are tested to determine if they are fit for use.
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TensorFlow is an open-source library and API designed for deep learning, written and maintained by Google. Use this tag with a language-specific tag ([python], [c++], [javascript], [r], etc.) for questions about using the API to solve machine learning problems. The programming languages that can be used with TensorFlow API vary, so you must specify the programming language. Please specify the application area such as [object-detection] as well.
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A block of arbitrary information, or resource for storing information, accessible by the string-based name or path. Files are available to computer programs and are usually based on some kind of persistent storage.
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Apache Spark is an open source distributed data processing engine written in Scala providing a unified API and distributed data sets to users for both batch and streaming processing. Use cases for Apache Spark often are related to machine/deep learning and graph processing.
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Swing is a user-interface toolkit in Java and is shipped with the standard Java SDK. It is contained within the package javax.swing.
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A template for creating new objects that describes the common state(s) and behavior(s). NOT TO BE CONFUSED WITH HTML CLASSES OR CSS CLASS SELECTORS. Use [html] or [css] instead.
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ASP.NET Core is a lean, composable, and cross-platform framework for building web and cloud applications. It is fully open-source on GitHub. ASP.NET Core apps can be run on Windows, Linux, or macOS.
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Sorting is the process of applying some order to a collection of items.
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A date is a reference to a particular day represented within a calendar system, and consists of year, month and day. Use for questions about creating, manipulating and storing date information. Use with any relevant language tags.
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