local storage is a new feature of HTML5 that basically allows you (a web developer) to store any information you want in your user’s browser using JavaScript.

Unless you need to store publicly available information that:

• Is not at all sensitive
• Doesn’t need to be used in an ultra high performance app
• Isn’t larger than 5MB
• Consists of purely string data

… don’t use local storage! Use the right tool for the job.