C++ 14 is basically a whole new language.
I first learned C++ is 2000 and most compilers didn’t even comply with the standard that had been recently published at the time. Now, we have not only got a much better standard, we also have compilers that are compliant! (Yes, even Microsoft’s)
Do you remember code full of double-pointers and pointers-by-reference? Well indulge in a bit of reading about copy constructors, move constructors, copy assignment and move assignment. Follow that up with some research into the new built-in smart pointer template types and finish off with some investigation into “elision” and return-value optimisation. Prepare to have your mind blown.