The scope of PHI can be broad; however, medical information that an employer receives in its role as an employer (and not as the sponsor or administrator of a group health plan), is generally not PHI subject to HIPAA.
Alphabetic characters are the 26 letters of the alphabet. Numeric's are the ten digits. Alphanumerics are both. Some of the special characters on a standard keyboard do not work for usernames or passwords.
Dim prefix As Char = a. Each possible value in a Char or String variable is a code point, or character code, in the Unicode character set. Unicode characters include the basic ASCII character set, various other alphabet letters, accents, currency symbols, fractions, diacritics, and mathematical and technical symbols.