Python is a multi-paradigm, dynamically typed, multipurpose programming language. It is designed to be quick to learn, understand, and use, and enforce a clean and uniform syntax. Please note that Python 2 is officially out of support as of 01-01-2020. Still, for version-specific Python questions, add the [python-2.7] or [python-3.x] tag. When using a Python variant or library (e.g. Jython, PyPy, Pandas, Numpy), please include it in the tags.
C# (pronounced "see sharp") is a high level, statically typed, multi-paradigm programming language developed by Microsoft. C# code usually targets Microsoft's .NET family of tools and run-times, which include the .NET Framework, .NET Core and Xamarin among others. Use this tag for questions about code written in C# or C#'s formal specification.
Android is Google's mobile operating system, used for programming or developing digital devices (Smartphones, Tablets, Automobiles, TVs, Wear, Glass, IoT). For topics related to Android, use Android-specific tags such as android-intent, android-activity, android-adapter, etc. For questions other than development or programming, but related to the Android framework, use this link: https://android.stackexchange.com.
CSS (Cascading Style Sheets) is a representation style sheet language used for describing the look and formatting of HTML (HyperText Markup Language), XML (Extensible Markup Language) documents and SVG elements including (but not limited to) colors, layout, fonts, and animations. It also describes how elements should be rendered on screen, on paper, in speech, or on other media.
Structured Query Language (SQL) is a language for querying databases. Questions should include code examples, table structure, sample data, and a tag for the DBMS implementation (e.g. MySQL, PostgreSQL, Oracle, MS SQL Server, IBM DB2, etc.) being used. If your question relates solely to a specific DBMS (uses specific extensions/features), use that DBMS's tag instead. Answers to questions tagged with SQL should use ISO/IEC standard SQL.
ASP.NET is a Microsoft web application development framework that allows programmers to build dynamic web sites, web applications and web services. It is useful to use this tag in conjunction with the project type tag e.g. [asp.net-mvc], [asp.net-webforms], or [asp.net-web-api]. Do NOT use this tag for questions about ASP.NET Core - use [asp.net-core] instead.
R is a free, open-source programming language and software environment for statistical computing, bioinformatics, visualization, and general computing. Please provide minimal and reproducible example(s) along with the desired output. Use `dput()` for data and specify all non-base packages with `library()` calls. Do not embed pictures for data or code, use indented code blocks instead. For statistics related questions, use https://stats.stackexchange.com.
C is a general-purpose programming language used for system programming (OS and embedded), libraries, games and cross-platform. This tag should be used with general questions concerning the C language, as defined in the ISO 9899 standard (the latest version, 9899:2018, unless otherwise specified — also tag version-specific requests with c89, c99, c11, etc). C is distinct from C++ and it should not be combined with the C++ tag absent a rational reason.
An array is an ordered data structure consisting of a collection of elements (values, variables or references), each identified by one or more indexes. When asking about specific variants of arrays, use these related tags instead: [vector], [arraylist], [matrix]. When using this tag, in a question which is specific to a programming language, tag the question with the programming language being used.
Do NOT use for questions about .NET Core - use [.net-core] instead. The .NET framework is a software framework designed mainly for the Microsoft Windows operating system. It includes an implementation of the Base Class Library, Common Language Runtime (commonly referred to as CLR), Common Type System (commonly referred to as CTS) and Dynamic Language Runtime. It supports many programming languages, including C#, VB.NET, F# and C++/CLI.
This tag should be used only on questions that are about Objective-C features or depend on code in the language. The tags [cocoa] and [cocoa-touch] should be used to ask about Apple's frameworks or classes. Use the related tags [ios], [macos], [apple-watch] and [tvos] for issues specific to those platforms.
Microsoft SQL Server is a relational database management system (RDBMS). Use this tag for all SQL Server editions including Compact, Express, Azure, Fast-track, APS (formerly PDW) and Azure SQL DW. Do not use this tag for other types of DBMS (MySQL, PostgreSQL, Oracle, etc.). Do not use this tag for issues on software and mobile development, unless it is directly related to the database.
Swift is a safe, fast, and expressive general-purpose programming language developed by Apple Inc. for its platforms and Linux. Swift is open-source. Use the tag only for questions about language features, or requiring code in Swift. Use the tags [ios], [ipados], [macos], [watch-os], [tvos], [cocoa-touch], and [cocoa] for (language-agnostic) questions about the platforms or frameworks.
Regular expressions provide a declarative language to match patterns within strings. They are commonly used for string validation, parsing, and transformation. Since regular expressions are not fully standardized, all questions with this tag should also include a tag specifying the applicable programming language or tool. NOTE: Asking for HTML, JSON, etc. regexes tends to be met with negative reactions. If there is a parser for it, use that instead.
Only for questions on programming against Excel objects or files, or complex formula development. You may combine the Excel tag with VBA, VSTO, C#, VB.NET, PowerShell, OLE automation, and other programming related tags and questions if applicable. General help regarding MS Excel for single worksheet functions is available at Super User.
DO NOT use this tag unless you are addressing Apple's iPhone and/or iPod touch specifically. For questions not dependent on hardware, use the tag [ios]. More tags to consider are [xcode] (but only if the question is about the IDE itself), [swift], [objective-c] or [cocoa-touch] (but not [cocoa]). Please refrain from questions regarding the iTunes App Store or about iTunes Connect. If using C#, tag with [mono].
The xml tag is used with questions about the use of the Extensible Markup Language (XML), a structured document format defining text encoding rules. When using this tag include additional tags such as programming language, tool sets, XML technologies being used, and other tags describing the environment of the problem posted. XML flexibility lends to a wide variety of uses for human and machine data transfer so be specific as to tools and libraries.
LINUX QUESTIONS MUST BE PROGRAMMING RELATED. Use this tag only if your question relates to programming using Linux APIs or Linux-specific behavior, not just because you happen to run your code on Linux. If you need Linux support you can try https://unix.stackexchange.com or the specific Linux distribution's Stack Exchange site like https://askubuntu.com or https://elementaryos.stackexchange.com/
A function (also called a procedure, method, subroutine, or routine) 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.
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.
PowerShell is a cross-platform command line and scripting utility from Microsoft. Use this tag for questions about writing and executing PowerShell scripts ONLY. Programming questions specific to the cross-platform version PowerShell Core (Windows, macOS, and Linux) should be tagged [powershell-core]. Questions about system administration should be asked on Super User or Server Fault.
THIS TAG IS PENDING REMOVAL. Instead, please use tags [excel] and [vba]. (More info: https://meta.stackoverflow.com/q/370095) Excel-VBA (Visual Basic for Applications for Microsoft Excel) is the dominant programming language for Microsoft Office Excel. It is an event-driven and object-oriented programming language for writing macros for Microsoft Office applications like Excel. DO NOT USE THIS TAG for VB.NET questions.
Docker is a tool to build and run containers. Questions concerning Dockerfiles, operations, and architecture are accepted. Questions about running docker in production may find better responses on ServerFault (https://serverfault.com/). The docker tag is rarely used alone and is often paired with other tags such as docker-compose and kubernetes.
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.
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.
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.
A data frame is a tabular data structure. Usually, it contains data where rows are observations and columns are variables of various types. While "data frame" or "dataframe" is the term used for this concept in several languages (R, Apache Spark, deedle, Maple, the pandas library in Python and the DataFrames library in Julia), "table" is the term used in MATLAB and SQL.
Comma-Separated Values or Character-Separated Values (CSV) is a standard "flat file database" format for storing tabular data in plain text, consisting of an optional header row that lists the table fields delimited by commas or tabs or other delimiter character, followed by one or more rows (newline separated) representing the table records as delimited lists of the values. Newlines and separator characters can appear within (quoted) fields.
Directory-level configuration file used by Apache web servers. Use this tag if and only if .htaccess content is directly involved in the topic. We know many people are using .htaccess, but kindly ask the members of the community to not use this tag, unless you know it is on-topic in your question.