Science Knowings: JavaScript Course For Social Media

Local Storage and Session Storage

Local Storage and Session Storage

Welcome to our session on Local Storage and Session Storage! Today, we'll dive into the world of web storage, where you can store data on the client side without relying on server-side databases.

Introduction to Local Storage and Session Storage

Local Storage and Session Storage are two browser-based storage mechanisms that allow you to store key-value pairs of data on the client side.

Local Storage stores data indefinitely, while Session Storage stores data only for the duration of the browser session.

Local Storage vs Session Storage: What's the Difference?

Feature Local Storage Session Storage
Lifespan Until manually cleared or browser data is deleted Only during the browser session
Scope Available to all tabs and windows Only available to the current tab
Size Limit 5MB (approx.) 5MB (approx.)

Advantages and Disadvantages of Local Storage and Session Storage

Advantages:

  • Easy to use and implement
  • Cross-browser compatibility
  • Stores data on the client side (reduces server load)

Disadvantages:

  • Limited storage capacity (5MB)
  • Security concerns (data can be accessed by malicious scripts)
  • Data is not synchronized across multiple devices

How to Use Local Storage

Set localStorage item:
localStorage.setItem('name', 'John');
Get localStorage item:
const name = localStorage.getItem('name');
Remove localStorage item:
localStorage.removeItem('name');

How to Use Session Storage

Set sessionStorage item:
sessionStorage.setItem('name', 'John');
Get sessionStorage item:
const name = sessionStorage.getItem('name');
Remove sessionStorage item:
sessionStorage.removeItem('name');

Best Practices for Using Local Storage and Session Storage

  • Use local storage for data that needs to persist across sessions.
  • Use session storage for data that is only relevant during the current session.
  • Consider using cookies or server-side storage for more sensitive data.

Applications of Local Storage and Session Storage

  • User preferences
  • Shopping cart contents
  • Login state
  • Game scores
  • Recently viewed products

When to Use Local Storage vs Session Storage

Use Local Storage when you need to persist data across sessions, such as user settings or preferences.

Use Session Storage when you need to store data that is only relevant during the current session, such as login status or shopping cart contents.

Common Use Cases for Local Storage

  • Storing user preferences (e.g., language, theme)
  • Keeping track of recent searches
  • Remembering login credentials

Common Use Cases for Session Storage

  • Tracking shopping cart items
  • Maintaining login status
  • Storing temporary data during form processing

Cross-Browser Compatibility

Local Storage and Session Storage are supported by all major browsers.

Security Considerations

Local Storage and Session Storage data can be accessed by malicious scripts.

Best practice: Use caution when storing sensitive information in local storage or session storage.

Next Topic: Cookies

In our next session, we'll explore the world of cookies, another important browser-based storage mechanism. Cookies are used to store small amounts of data on the client side for a specified period of time. Follow us to learn more!