My question is pretty straightforward, but to be more specific I want to quote 2 lines from [Stroustrup11](http://aksitha.com/Programming/C++/The%20C++%20Programming.Language.4th.Edition.Jun.2013%5BA4%5D.pdf).

1. `T[N]` A fixed-size built-in array: N contiguous elements of type T;
no `size()` or other member functions
2. `array<T,N>` A fixed-size array of N contiguous elements of type T;
like the built-in array, but with most problems solved

So what is the difference the author is mentioning? And what problems are solved for `std::array<T,N>` ?