let hoTen = "Nguyễn Văn A";
let tuoiNguoi = 25;
let laSinhVien = true;
let chuaCoGiaTri;
let giaTriNull = null; // Lưu ý: typeof null trả về 'object' - đây là một "lỗi lịch sử" của JavaScript
 
console.log(typeof hoTen);        // Output: string
console.log(typeof tuoiNguoi);    // Output: number
console.log(typeof laSinhVien);   // Output: boolean
console.log(typeof chuaCoGiaTri); // Output: undefined
console.log(typeof giaTriNull);   // Output: object (Hãy nhớ điều này!)
 

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