Python is an interpreted high-level general-purpose programming language. It is beginner-friendly and relatively easy to read and understand. Python is used a lot in Artificial Intelligence & Machine Learning, Data Science & Analysis, Robotics, Web Development, etc.
For use in Web Development, the most popular Python framework is Django which encourages rapid development and clean, pragmatic design. Others include Flask, CherryPy, Web2py, etc.
Python is one of the most used languages for programming Raspberry Pi.
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C++ is a general-purpose programming language created by Bjarne Stroustrup as an extension of the C programming language. C and C++ are a few of the preferred languages for developing computer programs, libraries, Operating Systems, compilers, etc. C/C++ works very close to the hardware and they are preferred in Hardware Engineering.
C/C++ are also hugely used in Telecommunication Systems, Embedded Systems, Control Systems, Predictive maintenance, Game Development, Artificial Intelligence, space probes, etc.
In Game Development, Unreal Engine uses C++ for programming game logic.
Qt uses C++ for Desktop, Mobile apps, and embedded systems development
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C# is a general-purpose, multi-paradigm programming language encompassing static typing, strong typing, lexically scoped, imperative, declarative, functional, generic, object-oriented, and component-oriented programming.
C# (C-Sharp) was developed by Microsoft and runs on the .NET Framework. C# is used to develop web apps, desktop apps, mobile apps, games and much more.
The most popular Game Engine Unity uses C# for game development
Java is a class-based, object-oriented programming language that is designed to have as few implementation dependencies as possible. It is used to develop Desktop and mobile applications, big data processing, embedded systems, etc.
According to Oracle (the company that owns Java), Java runs on 3 billion devices worldwide, making it one of the most popular programming languages in the world.
Java is intended to let application developers write once, and run anywhere (WORA).
Java is one of the two principle Languages used in Android Studio for Android mobile applications development, the other being Kotlin.