There are several common validation techniques used in email marketing forms:
Email Address Validation: Ensures that the email address entered is in the correct format (e.g., user@example.com). Phone Number Validation: Checks that the phone number is in the correct format and length. CAPTCHA: Prevents spam submissions by requiring users to complete a challenge. Password Strength Check: Ensures that passwords meet security requirements (e.g., minimum length, special characters).