[[Rust]]
[[Boxes live in the heap]]


---

The stack consists of frames.

Frames are just mappings of names to values within a single scope, they are tightly coupled to a specific function

Freeing is the act of discarding such a frame.

If we assign a variable such as 
```rust
let a = [0; 1_000_000];
let b = a;
```

the value of a is **copied** to b (thus we get two huge arrays). This is **expensive**. Think about what happens when we call a function.