Actually more than 90% sofware in the market is being develop with C or C++. C also being used to develop core software for automatic machine such as washing machine,aircond,etc that based on PIC (Programable Interface Controller - or single chip computer).
An example software that being develop using C/C++ inside the computer is like Microsoft Windows , Microsoft Office, Internet Explorer, Microsoft Visual Studio (including VB compiler) and many more.

Believe it or not, actually it almost no commercial software that professionally being develop using another language such as VB.VB actually use for the final project for student not for commercial

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