This is an excellent question. Zero-length arrays, also known as flexible arrays, are used to implement variable-length arrays, primarily in structures.

Structures (or “structs” in C) allow you to group several related variables and treat them as one unit. They are a mechanism for extending the type system of the C language by introducing user-defined ...

Programming C without variables is like, well, programming C without variables. They are so essential to the language that it doesn’t even require an analogy here. We can declare and use them… ...