This test checks to see if window.localStorage, window.sessionStorage and window.onstorage exist. window.sessionStorage exists Storage object sessionStorage has length Storage object sessionStorage has key Storage object sessionStorage has getItem Storage object sessionStorage has setItem Storage object sessionStorage has removeItem Storage object sessionStorage has clear window.sessionStorage == window.sessionStorage: true window.sessionStorage === window.sessionStorage: true window.localStorage exists Storage object localStorage has length Storage object localStorage has key Storage object localStorage has getItem Storage object localStorage has setItem Storage object localStorage has removeItem Storage object localStorage has clear window.localStorage == window.localStorage: true window.localStorage === window.localStorage: true window.onstorage exists