A PIN, or Personal Identification Number, is a numeric code used to authenticate a user’s identity. It is commonly used in banking, mobile devices, and online accounts to provide an extra layer of security. Users typically create their own PINs, which usually consist of four to six digits. When entering a PIN, it is important to keep it confidential to prevent unauthorized access. Many systems will lock an account after several incorrect attempts to enter the PIN, helping to protect sensitive information. PINs are often used alongside other security measures, such as passwords or biometric verification, to enhance security further.