What does a type followed by _t (underscore-t) represent?

Question

This seems like a simple question, but I can\'t find it with the Stack Overflow search or Google. What does a type followed by a _t mean? Such as

Answer 1

It's a convention used for naming data types, e.g with typedef:

typedef struct {
  char* model;
  int year;
...
} car_t;