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.
This section contains information of how user agents should treat control characters and other special characters. The characters between the tags represent text encoded according to ISO 8859/1 8-bit single-byte coded graphic character set known as Latin Alphabet No. 1, or simply Latin-1. There are 256 character positions in the Latin-1 encoding.