C 
Powerful and highly portable, C remains one of the world's most popular programming languages--though its procedural nature makes C programs much harder to modify or repurpose than those written in object-oriented languages. C programs can be very compact, making them ideal for operating systems or embedded software. The first significant program created in C was the Unix operating system. For application development, C has been largely succeeded by C++, which wraps the power of C in object-oriented programming methods.