12. What's the difference between local storage and session storage?

sessionStorage i localStorage are data containers, provided to application by browser. It holds data in text format as a key/value pairs. It's size depends on browser.

They share same API:

• setItem(key, value) - ustawia wartość value pod kluczem key
• getItem(key) - zwraca wartość spod klucza key
• removeItem(key) - usuwa wartość spod klucza key
• clear() - czyści pamięć.

Differences:

Session Storage:

• Cleared on closing tab/browser
• About 5MB memory
• Is not shared between browser's tabs, even if they are under same domain

Local Storage:

• It's not cleared automatically - it has to be cleared manually in devtools, in browser's settings or from code
• About 5-10MB memory
• Browser's tab share it if they are under same domain