the first one char city[] = {'D', 'a', 'l', 'l', 'a', 's'};
will just be a character array as there is no \0 at the end
and char city[] = "Dallas";
can be said to be a c style string
if you put char char city[] = {'D', 'a', 'l', 'l', 'a', 's','\0'};
then both will be same