localStorage & sessionStorage

The Web Storage API provides mechanisms by which browsers can store key/value pairs, in a much more intuitive way than using cookies. There are two main mechanisms within this API: `localStorage` and `sessionStorage`. Both provide a simple interface with methods like `setItem(key, value)`, `getItem(key)`, `removeItem(key)`, and `clear()`. The key difference between them is persistence. Data stored in `localStorage` is persistent. It remains available even after the browser window is closed and reopened. It has no expiration time and will stay until it is explicitly cleared by the user or web application. This makes it suitable for storing user preferences, a JWT token, or a theme setting (like dark/light mode). Data stored in `sessionStorage`, however, is only available for the duration of the page session. A page session lasts for as long as the browser is open and survives over page reloads and restores. Closing a tab or window will clear the session storage for that session. This makes it useful for storing temporary data that should not persist between visits, such as data for a multi-step form. It's important to remember that both store data as strings, so if you want to store objects, you must `JSON.stringify` them before setting and `JSON.parse` them after getting.