Explain the difference between localStorage, sessionStorage, and cookies in HTML5.
Instruction: Describe the functionalities and differences of localStorage, sessionStorage, and cookies.
Context: The question tests the candidate's knowledge of client-side storage mechanisms provided by HTML5 and their ability to distinguish between them in terms of scope, lifecycle, and capacity.
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localStorage and sessionStorage are synchronous string key/value stores. They are not automatically attached to HTTP requests. Both use origin boundaries, subject to browser storage/privacy policy; sessionStorage additionally separates top-level browsing contexts.
localStorage can persist across sessions but has no guarantee against deletion, eviction or access denial. sessionStorage survives reloads during a page session and normally ends with that tab's session...