js-examples/localStorage

localStorage

Javascript has an API called localStorage that let's you store some data in the browser in between sessions, the idea is similar to storing a cookie but it has no expiry date and can store some more data. It is useful to save configuration of web applications, personal preferences, etc. There's no specc'ed limit to how much data the browser let's you store but most common implementations (e.g. Chrome) limit localStorage to 10MB, some documentation says 5MB.

To look at the contents of the localStorage database in your browser, you can open the developer tools and in the storage section you should find something like this:

Read more about localStorage in the spec.