Xcode is Apple's integrated development environment (IDE) for macOS, used to develop software for macOS, iOS, iPadOS, watchOS, and tvOS. It was first released in 2003; the latest stable release is version 12.3, released on December 14, 2020, and is available via the Mac App Store free of charge for macOS Big Sur users. Registered developers can download preview releases and prior versions of the suite through the Apple Developer website. Xcode includes Command Line Tools (CLT), which enable UNIX-style development via the Terminal app in macOS. They can also be downloaded and installed without the main IDE.