# char* -> string
string name = "World"s + " hello"; // теперь есть буква "s", которая на самом деле ф-я()
wstring name = L"World"s + L" hello";
u32string name = U"World"s + U" hello"; // utf32
const char* s = "Hello, World!";
string str(s); // там свой конструктор

#include <iostream>
#include <string>
#include <cstddef>

int main ()
{
  std::string str ("The sixth sick sheik's sixth sheep's sick.");
  std::string key ("sixth");

  std::size_t found = str.rfind(key);
  if (found!=std::string::npos)
    str.replace (found,key.length(),"seventh");

  std::cout << str << '\n';
}

char *p;

# НЕЛЬЗЯ!!!
printf(p);

# МОЖНО:
printf("%s", p);

#include <sstream>
#include <string>
#include <iostream>
 
int main()
{
    std::stringstream stream;
    std::string str{"String"};
    stream << "Some " << str;
    std::cout << stream.str() << "\n"; // Some String
}