Add JavaScript questions (#4505)

* Add Javascript questions * wip: add more questions * wip: add ternary operator * wip: add more questions * wip: add more questions * wip: add more questions * wip: add more questions * fix: set example * wip: add more questions * wip: add more question * wip: add more questions * wip: add more questions * wip: add more questions * wip: add more questions * wip: add more questions * wip: add more questions * wip: add more questions * wip: add another question * wip: add more questions * wip: add more questions * wip: add more questions * wip: add more questions * wip: add more questions * wip: add more questions * wip: add more questions * wip: add more questions
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+The Event loop has two main components: the Call stack and the Callback queue.
+
+## Call Stack
+
+The Call stack is a data structure that stores the tasks that need to be executed. It is a LIFO (Last In, First Out) data structure, which means that the last task that was added to the Call stack will be the first one to be executed.
+
+## Callback Queue
+
+The Callback queue is a data structure that stores the tasks that have been completed and are ready to be executed. It is a FIFO (First In, First Out) data structure, which means that the first task that was added to the Callback queue will be the first one to be executed.
+
+## Event Loop's Workflow:
+
+1. Executes tasks from the Call Stack.
+2. For an asynchronous task, such as a timer, it runs in the background. JavaScript proceeds to the next task without waiting.
+3. When the asynchronous task concludes, its callback function is added to the Callback Queue.
+4. If the Call Stack is empty and there are tasks in the Callback Queue, the Event Loop transfers the first task from the Queue to the Call Stack for execution.
+
+```js
+setTimeout(() => console.log('Hello from the timer'), 0);
+console.log('Hello from the main code');
+```
+
+1. `setTimeout` is processed, and because it's asynchronous, its callback is placed in the Callback Queue.
+2. The next line, `console.log("Hello from the main code")`, is logged immediately.
+3. Although the timer duration is 0 milliseconds, its callback has to wait until the Call Stack is empty. After the main code logs, the callback is moved from the Callback Queue to the Call Stack and executed.
+4. The result is "Hello from the main code" being logged before "Hello from the timer".