Create and test regular expressions for pattern matching
^[^\s@]+@[^\s@]+\.[^\s@]+$Matches valid email addresses
^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)...Min 8 chars with uppercase, lowercase, digit, special
^(\+?1[-.\s]?)(\([0-9]{3}\)|[0-9]{3})US phone format with variations
^(https?:\/\/)?(www\.)?[-a-zA-Z0-9@:%._\+~#=]...Matches HTTP and HTTPS URLs