In C programming, a string is a sequence of characters terminated with a null character \0. A string in C is stored as an array of characters, and the difference between a character array and a C string is that the string is terminated with a unique character \0. Declaring a string in C is as simple as declaring a one-dimensional array. The basic syntax for declaring a string is `char string_name. There is an extra terminating character which is the Null character (\0) used to indicate the termination of a string that differs strings from normal character arrays.

In C, a string is simply an array of characters, ending with a null byte. So a char* is often pronounced "string" when youre reading C code.

Therefore, a string in C is a sequence of characters stored as an array of characters, terminated with a null character.