Mutable

const student = { name: 'Sheldon', score: 100, grade: 'A', } console.log(student) // { name: 'Sheldon', score: 100, grade: 'A' } delete student.score student.grade = 'F' console.log(student) // { name: 'Sheldon', grade: 'F' } student = {} // TypeError: Assignment to constant variable.