Cookies, sessionStorage, and localStorage are all ways to store data in a web browser, but they have some important differences in terms of functionality and lifespan.
Cookies
Cookies are small text files that are stored on a user's computer by a website. They can be used to store information such as login credentials, preferences, or shopping cart contents. Cookies are sent back to the website that created them with each request, which allows the website to keep track of the user's state and preferences. They have a set expiry date and can be deleted by the user.
SessionStorage and localStorage, on the other hand, are both types of web storage that allow websites to store data directly in the browser. The main difference between the two is that sessionStorage only stores data for a single browser session, while localStorage stores data permanently until it is explicitly deleted by the user or the website.
SessionStorage
SessionStorage is useful for storing temporary data that should only be available during the current browsing session. For example, you might use sessionStorage to store a user's login credentials until they log out or close the browser. Once the browser is closed, the data in sessionStorage is deleted.
LocalStorage
LocalStorage, on the other hand, can be used to store data that needs to persist across browser sessions. For example, you might use localStorage to store a user's preferences or settings so that they are still available when the user returns to the website at a later time.
It's important to note that both sessionStorage and localStorage have the same security limitations as cookies and can be accessed by any script on the same domain.
In summary, cookies, sessionStorage, and localStorage are all ways to store data in a web browser, but they have different functionalities and lifetimes. Cookies are sent back to the website with each request, they have expiry date, and can be deleted by the user. SessionStorage stores data for a single browser session and is deleted when the browser is closed. LocalStorage stores data permanently until it is explicitly deleted by the user or the website.