the book should mention the difference between vectors and arrays.

[bharadwaj6]

I have found out that vectors are heap allocated whereas arrays are stack allocated, but this was not mentioned anywhere in the book.

[kmcallister]

Arrays are allocated directly within the containing structure. So Box<[u8; 3]> is heap allocated, but let x: [u8; 3] = ... is stack-allocated like any let variable.

[bharadwaj6]

Let me summarize it here: So unless we box the array declaration, arrays would be allocated on the stack, whereas vectors would always be allocated on the heap (possibly because they are implemented as box types in vec!?). Correct me if I am wrong here.

[steveklabnik]

Yes.