Web pages become interactive when JavaScript responds to user actions like clicks or typing.

To handle user actions, use the addEventListener() method.

const button = document.querySelector(".btn");

button.addEventListener("click", () => {
  console.log("Button clicked");
});

When the button is clicked, the function runs.

Common events:

• "click": when an element is clicked;
• "input": when a user types in a field;
• "submit": when a form is submitted.

Example with user input:

const input = document.querySelector("input");

input.addEventListener("input", () => {
  console.log(input.value);
});

JavaScript listens for events and runs code in response, which makes web pages interactive.