eolas/Software_Engineering/Call_stack.md

---
category: Software Engineering
tags:
  - callstack
---

# The call-stack

A [stack](/Data_Structures/Stacks.md) data structure that holds the information of the functions called within a program that allows transfer of the application control from these functions to the main process after code inside the functions has been executed.

## Example

```js
function greet(who) {
  console.log('Hello ' + who);
}

greet('Harry');

console.log('Bye');
```

### Breakdown

1. Interpreter receives call to `greet()`
2. Goes to the definition of this function (`function greet(who)...`)
3. Executes the `console.log` within this function
4. Returns to the location that called it (`greet("Harry")`)
5. Finds that there is nothing else to do in this function so moves to next function: the `console.log("bye")`
6. Executes
7. Returns to line that called it. Finds nothing else to do. Exits program.