HTML local storage, better than cookies.
With local storage, web applications can store data locally within the user's browser.
Before HTML5, application data had to be stored in cookies, included in every server request. Local storage is more secure, and large amounts of data can be stored locally, without affecting website performance.
Unlike cookies, the storage limit is far larger (at least 5MB) and information is never transferred to the server.
Local storage is per domain. All pages, from one domain, can store and access the same data.
Local storage is supported in Internet Explorer 8+, Firefox, Opera, Chrome, and Safari.
Note: Internet Explorer 7 and earlier versions, do not support Web Storage.
HTML local storage provides two objects for storing data on the client:
Before using local storage, check browser support for localStorage and sessionStorage:
The localStorage object stores the data with no expiration date. The data will not be deleted when the browser is closed, and will be available the next day, week, or year.
The example above could also be written like this:
The syntax for removing the "lastname" localStorage item is as follows:
Note: Name/value pairs are always stored as strings. Remember to convert them to another format when needed!
The following example counts the number of times a user has clicked a button. In this code the value string is converted to a number to be able to increase the counter:
The sessionStorage object is equal to the localStorage object, except that it stores the data for only one session. The data is deleted when the user closes the browser window.
The following example counts the number of times a user has clicked a button, in the current session: