JavaScript BOM (Browser Object Model)

The Browser Object Model (BOM) allows JavaScript to interact with the browser itself, not just the webpage.

Through BOM, JavaScript can:

✔ Control browser windows
✔ Access browser history
✔ Work with URL and location
✔ Detect browser information
✔ Access local/session storage

📌 window Object

The window object is the top-level object in the browser.
Everything in BOM is part of window.

Example:

🧱 Key BOM Components

🔹 1. window.alert() – Show Message Box

🔹 2. window.confirm() – Ask Yes/No Question

If user clicks:

• ✔ OK → true

• ❌ Cancel → false

🔹 3. window.prompt() – Input From User

🔹 4. window.open() and window.close()

🔹 5. window.setTimeout() — Delay Execution

🔹 6. window.setInterval() — Repeat Execution

🌐 Location Object

Used to work with the current URL.

Redirect to another page:

⏮ History Object

Used to navigate browser history.

📁 Navigator Object

Gives browser and device info.

💾 Storage (Web Storage)

Local Storage (saved permanently)

Session Storage (removed after tab closes)

🚀 Summary Table