What are the differences between cookies and local storage?

What are the differences between cookies and local storage?

Cookies and local storage are both used to store data in the browser, but they have key differences. Cookies are sent to the server with every HTTP request, while local storage is only accessible on the client side. Additionally, cookies have a size limit of about 4KB, whereas local storage can hold up to 5-10MB of data.

Can you explain how long the data lasts in each?

Cookies can have an expiration date set, after which they are deleted. Local storage, on the other hand, persists until it is explicitly deleted by the user or the application.

Which one is better for storing user preferences?

Local storage is generally better for storing user preferences due to its larger capacity and the fact that it doesn't get sent with every request, making it more efficient.

Are there any security concerns with either?

Yes, cookies can be vulnerable to cross-site scripting (XSS) attacks if not properly secured. Local storage is also susceptible to XSS, but it does not have the same security features as cookies, like the HttpOnly flag.