There are many languages to choose from for desktop application development, here are some common ones:
C#: C# is a modern, general-purpose programming language that is one of the main languages of the .NET platform. Using C#, you can develop Windows desktop applications, MacOS desktop applications, and cross-platform applications.
Java: Java is a widely used programming language that has cross-platform features and can be used to develop desktop applications for different operating systems such as Windows, MacOS, and Linux.
C++: C++ is a general-purpose programming language and the language of choice for many desktop applications. It has high performance and low-level control capabilities, and supports multi-platform development.
Python: Python is an easy-to-learn programming language that can also be used for desktop application development. It has rich libraries and frameworks that simplify the development process.
Swift: Swift is a modern programming language introduced by Apple Inc., which is specially used for developing MacOS and iOS applications. If your goal is to develop desktop applications limited to MacOS, Swift is a good choice.
JavaScript: JavaScript is commonly used to develop web applications, but it can also be used for desktop application development using tools such as Electron. Electron lets you build cross-platform desktop applications using HTML, CSS, and JavaScript.
These are just some common languages, there are others to choose from, depending on your needs, technology stack and personal preference.