@Hareen-Laks @dheerendra If you are developing an application for Mobile Devices, there will be many different Operating Systems like one device will be having Android, one will be having iOS etc.., So you need to write code specific to each Operating System which is time consuming and it is very costly. So there arises a thought that "Can we write code once and use on different Operating Systems..?" The answer is YES, with the help of Cross platform libraries. And Qt Framework is the one which provides Cross Platform Libraries for developing Apllications across different sets of Platforms.