What languages ​​are used to create applications?

Question

Programming languages

Do they use the same programming languages ​​to create software, applications, games and create an OS?

Answer 1

OSes are most often written in low-level languages ​​like C (Linux, FreeBSD), C++ (Windows), Rust (Redox). Sometimes assembler inserts are used.
Games (meaning 3D games) are most often written in C ++, but it is also possible in C # (Unity), JS (Unity or something that simplifies working with WebGL). Although there may be other languages ​​(for example, minecraft is written in JAVA, and the good old Doom is written in C). You will also need a shader language for programming a video card, for example, for OpenGL and WebGL, this language is GLSL.
Applied software is generally written in anything, the choice of language depends on the task. But in some areas, leaders can still be distinguished:
Enterprise solutions - Java EE, less often C #
Desktop software for Windows - C # (less often other languages ​​of the .net platform)
Desktop software for MacOS - Swift
Cross-platform desktop software - Java, Python, JS (Electron)
Android mobile software - Kotlin, Java
iOS mobile software - Swift
Cross-platform mobile software - C# (Xamarin), JS (Cordova, ReactNative, etc.)
Server software - php, Python , Ruby, JS (node), Java, Go, Rust, ... there are many options
Browser software - JS or what compiles to JS (more often TypeScript)

Answer 2

List of programming languages .
Almost any task can be performed on almost any PL.
The only question is expediency. Few people will write a website in C++, just as few people will write a desktop application with an interface in PHP.