There are four type of data in C. They are Basic which contains int, float, double, char, short int and long int, then Derived which are Array, Pointer, Structure and Union, then Void which means no type and at last Enumeration, it is used to define a value with a number to reference. To get more knowledge or want to learn the C from beginner level check out this book : https://amzn.to/3uOWPUi