{ name: "drew", age: 30 } groups related data. Access with dot (obj.name) or bracket (obj["name"], needed for dynamic or non-identifier keys). Objects are reference types: copying the variable copies the reference, not the data. Add, change, and delete properties freely.
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<script>const u={name:'drew'}; u['role']='admin'; delete u.name;
document.getElementById('o').textContent=JSON.stringify(u);</script></body></html>