Atom

Real World Example

Imagine trying to fix a jigsaw puzzle when you're missing just one tiny piece. Just like that missing piece is crucial to completing the entire picture, an atom is the tiniest part that makes up an element, essential for its identity. Each piece in a puzzle is unique and fits into a specific place, just as each type of atom has unique properties that define the element it composes; without that one piece (or atom), the whole structure can't be complete or function properly.