JavaScript localStorage, cookies, IndexedDB, and browser persistence

Browser storage lessons and concepts

1. Cookies and document.cookie

   Understand browser cookies, document.cookie syntax, expiration, paths, and the limits of string-based cookie storage.

   Outcome: Read and write small browser cookie values deliberately.

   • JavaScript cookies
   • document.cookie
   • browser cookies
   Study Cookies, document.cookie

2. localStorage and sessionStorage

   Use Web Storage APIs to keep simple string data across reloads or within one browser session.

   Outcome: Persist lightweight client-side state without a backend.

   • localStorage JavaScript
   • sessionStorage
   • Web Storage API
   Study LocalStorage, sessionStorage

3. IndexedDB

   Store larger structured browser data using IndexedDB transactions, object stores, indexes, and asynchronous APIs.

   Outcome: Choose IndexedDB when localStorage is too small or too synchronous.

   • IndexedDB JavaScript
   • browser database
   • client-side database
   Study IndexedDB

4. JSON serialization

   Serialize arrays and objects before saving them in browser storage or sending them through network requests.

   Outcome: Store and restore structured JavaScript values safely.

   • JSON JavaScript
   • JSON stringify
   • JSON parse
   Study JSON methods, toJSON

5. Browser environment

   Connect storage APIs with the browser runtime, window object, document, and web platform constraints.

   Outcome: Understand where browser storage APIs live and how scripts access them.

   • browser JavaScript
   • window object
   • browser APIs
   Study Browser environment, specs

6. Fetch and stored data

   Combine network responses with storage by parsing API data and caching useful values in the browser.

   Outcome: Move data between APIs, JSON, and client-side storage with clear boundaries.

   • JavaScript fetch
   • cache API data
   • browser persistence
   Study Fetch