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Version: v5


Android SDK

The Android SDK is a software development kit built for developers building for Google's Android Platform. It includes tools for building, testing, and debugging Android applications.

Android Studio

Android Studio is the official Integrated Development Environment (IDE) for Native Android app development.


Autoprefixer is a tool that adds vendor-specific-prefixes to hand-written Sass/CSS code. This ensures that standardized CSS rules you write will be applied across all supporting browsers. For example, instead of having to know every flexbox syntax used by various browsers, autoprefixer allows you to just write display: flex; and it'll automatically plug in the correct CSS.


Bundling is the process of taking an app's dependencies (code you've written plus any npm modules installed) and compiling/transpiling them down to one single file.


Capacitor is an open source cross-platform app runtime that allows web-based apps to run natively on iOS, Android, Electron, and the web. It's helpful to refer to these apps "Native Progressive Web Apps" and they represent the next evolution beyond the traditional Hybrid app mentality. Capacitor was created and is actively developed/supported by Ionic, the company.


A CLI, or Command-Line Interface, is a text-based interface for interacting with a program. The common command-line app for a Mac user is the Terminal app, and Windows users often use Command Prompt. The Ionic community often uses this term to refer to Ionic's CLI. Ionic's CLI can be used for a number of things, such as creating production builds of an app, running the development server, and accessing Ionic commercial services.


CommonJS is a group that defines standard formats for JavaScript APIs. They have defined standards for JavaScript modules and packages.


Apache Cordova is an open source mobile application development framework that transforms standard HTML/CSS/JS into full-fledged native apps. It provides a JavaScript API for accessing native device functionality, such as the camera or accelerometer. Cordova contains the necessary build tools for packaging webapps for iOS, Android, and Windows Phone.


CORS (Cross-Origin Resource Sharing) is a mechanism for servers to control client access to web assets. See the CORS FAQs for more information.

CSS Variables

You may be familiar with variables from Sass. CSS Variables enable the same functionality but are built into the browser. CSS Variables are available in all evergreen browsers.


Decorators are expressions that return a function. They allow you to take an existing function, and extend its behavior. With TypeScript, you can also decorate classes and parameters. When you decorate a class, you are wrapping and extending the behavior of its constructor. In other words, the decorator will add some functionality when the constructor is called, and will then return the original constructor. When you decorate a parameter, you are wrapping the argument that gets passed in for that parameter. The decorator will add functionality when an argument is passed to the method, and then return the original argument.


ES5 refers to EcmaScript 5th Edition. A simple way to put it is that ES5 is the version of JavaScript which developers are most familiar with today.


A wide range of new features were introduced in this version of JavaScript, including classes, modules, iterators, and promises. Evergreen browsers (Chrome, Safari, Firefox and Edge) have full support for ES6, but to use ES6 features in older browsers, tools such as Babel and TypeScript have to transpile ES6 code down to ES5.


This version of JavaScript added a number of new features to the language, including Array.includes and the exponentiation operator. This version of JavaScript is fully supported by all evergreen browsers (Chrome, Safari, Firefox and Edge)


This version of JavaScript is the latest standard. It is currently in the final stage before becoming the new official standard. This spec includes Async/Await (already in all evergreen browsers) and shared memory/atomics.


Genymotion is a third-party Android emulator. It is extremely fast, and is useful for quickly testing your app on Android. Check out our resource section on Genymotion for more info.


Git is a distributed version control system for managing code. It allows development teams to contribute code to the same project without causing code conflicts.


Gulp is a tool for running tasks which can be used to build your app. Common build tasks include transpiling ES6 to ES5, turning Sass into CSS, minifying code, and concatenating files.

ES Modules

ES Modules brings the concept of modules natively to JavaScript. With modules, classes and variables are no longer in the global scope and have to be explicitly imported into your project to be used. This makes it much easier to understand where your code is coming from and increases modularity and compartmentalization of functionality.


Ionicons is an open-source icon set used and created by Ionic. It includes 1:1 iOS and Material Design icons, as well as commonly used social/application icons. Ionicons is included by default in Ionic distributions, but they can also be used in any project.


Karma is a test runner that will run an app's test inside a real browser. It executes test cases, written in any testing framework, in a real browser. Karma was originally written for use with Angular 1.


Modules in JavaScript are small, independent, and reusable pieces or code that are isolated from one another and the Global scope.


A monorepo is a single git repository with multiple projects. Advantages include simpler organization, shared tooling and dependencies, and better collaboration with teammates.

Live Reload

Live Reload (or live-reload) is a tool that automatically reloads the browser or Web View when it detects changes in your app. In some cases, it can replace parts of your app without having to reload the entire window. See the Live Reload docs for more information.


Node is a runtime environment that allows JavaScript to be written on the server-side. In addition to being used for web services, node is often used to build developer tools, such as the Ionic CLI.


npm is the package manager for node. It allows developers to install, share, and package node modules. Ionic can be installed with npm, along with a number of its dependencies.


An observable is an object that emits events (or notifications). An observer is an object that listens for these events, and does something when an event is received. Together, they create a pattern that can be used for programming asynchronously.

Package ID

Referred to by Apple as Bundle ID and by Android as Application ID, the Package ID is used for identifying apps published to the App Store/Play Store. It is a string formatted in reverse-DNS notation.


A polyfill is a bit of code that adds functionality to the browser and normalizes browser differences. This is similar to a shim, but where a shim has it's own API, a polyfill let's the expect API of the browser be used.


Protractor is a testing framework written for and by the Angular team. Protractor can be used with test runners, like Karma, for end-to-end testing. Test runners allow you to quickly and programmatically verify code quality.


Sass is a stylesheet language that compiles to CSS and is used by Ionic. Sass is like CSS, but with extra features such as variables, mixins, and loops.

Scoped Encapsulation

A component that uses scoped encapsulation will automatically scope its CSS by appending each of the styles with a data attribute at run time. Overriding scoped selectors in CSS requires a higher specificity selector. Scoped components can also be styled using CSS Custom Properties.

Shadow DOM

Shadow DOM is a native browser solution for DOM and style encapsulation of a component. It shields the component from its surrounding environment. To externally style internal elements of a Shadow DOM component you must use CSS Custom Properties or CSS Shadow Parts.


A shim is a piece of code that normalizes an APIs across browsers. A shim can have it's own API that hides the browser specific implementation from the end user.


Transpilation is the process of converting code from one language to another language prior to execution. Typically, a transpiler will convert a high-level language to another high-level language. The most common type of transpilation in Ionic Framework is converting ES2015/ES6 (TypeScript) to ES5 (traditional JavaScript).


TypeScript is a superset of JavaScript, which means it gives you JavaScript, along with a number of extra features such as type declarations and interfaces. Although Ionic is built with TypeScript, using it to build an Ionic app is completely optional.

Unit Tests

Unit Tests and unit testing are a way to test small pieces of code to see if they behave as expected. Unit testing frameworks include Jasmine, Mocha, QUnit, and many others.


Webpack bundles together JavaScript modules and other assets. It can be used to create single or multiple "chunks" that are only loaded when needed. Webpack can be used to take many files and dependencies and bundle them into one file, or other types.

Web Standards

The World Wide Web Consortium (W3C) is the standards organization for the Web. Together, industry leaders and the public work together to develop web standards, which are a set of protocols, specifications, and technologies that define the Web Platform.


Xcode is an Apple IDE (integrated development environment) for software development on Apple operating systems (macOS, iOS, watchOS and tvOS), with extensions available for other languages and platforms.