Why declaring an arrray of strings with a pointer? What really happens when doing it? [duplicate]

Fundamentally, a string in C is an array of char.

Because of the correspondence between arrays and pointers in C, it is very common and very convenient to refer to an array using a pointer to its first element.

So although strings are fundamentally arrays of char, it is very common to refer to them using pointers to char.

So char *arr[] (which has type "array of pointer to char") is a good way to implement an array of strings.

You can't write

char arr[] = {"PYTHON", "JAVA", "RUBY", "C++"}; 

because it's a type mismatch (and correspondingly meaningless). If you declare an array of char, the initializer for it must be characters. So you could do

char arr[] = { 'P', 'Y', 'T', 'H', 'O', 'N' }; 

Or, as a special shortcut, you could do

char arr[] = "PYTHON"; 

where the initializer is a single string literal. This string literal is an array of char, so it's a fine initializer for arr which is an array of char. But there's no direct way to pack multiple strings (as in your original question) into a single array of char.

Of course, there's one more issue, and that's null termination. More precisely, a string in C is a null terminated array of char. So the "special shortcut"

char arr[] = "PYTHON"; 

is actually equivalent to

char arr[] = { 'P', 'Y', 'T', 'H', 'O', 'N', '\0' };