A PIN, or Personal Identification Number, is a unique numeric code used to authenticate a user’s identity. It is commonly used in banking and security systems to protect access to accounts and sensitive information. Users typically create their own PINs, which usually consist of four to six digits, making them easy to remember but difficult for others to guess. When accessing an ATM or making a purchase with a debit or credit card, users are prompted to enter their PIN. This process helps ensure that only the authorized person can access their funds or personal data. Keeping a PIN secure is essential to prevent unauthorized access to accounts.