Would someone please explain this:
"C++, pronounced "C plus plus," is a programming language that was built off the C language".
What is meaning of "off" in this statement?
The phrase built off is another way of saying built on, which means adding on to something that already exists.
As the inventor of C++, Bjarne Stroustrup, explains in one of his books, he added Simula-style classes to C to create "C With Classes," which became C++:
I originally designed and implemented [C++] because I wanted to distribute the services of a UNIX kernel across multiprocessors and local-area networks (what are now known as multicores and clusters). For that, I needed some event-driven simulations for which Simula would have been ideal, except for performance considerations. I also needed to deal directly with hardware and provide high-performance concurrent programming mechanisms for which C would have been ideal, except for its weak support for modularity and type checking. The result of adding Simula-style classes to C, “C with Classes,” was used for major projects in which its facilities for writing programs that use minimal time and space were severely tested. The name C++ (pronounced “see plus plus”) was coined by Rick Mascitti in the summer of 1983 and chosen as the replacement for “C with Classes” by me.
This actually implies that C++ was built from, as in an offshoot or supplement to the C language