History of the Greek alphabet retained the sound. A symbol based on the left-hand half ( ├ ) of the letter Η was therefore sometimes used to indicate the presence of where necessary, and its absence was indicated by a symbol based on the right half. During the classical period, ΕΙ came to be pronounced and ΟΥ came to be pronounced , Υ having meanwhile moved to . By about 200 BC, a system of diacritical marks was invented, representing the tone accents in use in Ancient Greek. This also helped to indicate the length of the vowels Α, Ι, and Υ in certain cases
Violent Gang and Terrorist Organization File Violent Gang and Terrorist Organization File The NCIC Violent Gang and Terrorist Organization File (VGTOF) was designed to provide identifying information about violent criminal gangs and terrorist organizations and their members to a wide variety of law enforcement personnel. This information warns law enforcement officers of the potential danger posed by violent individuals and to promote the exchange of information about these organizations and members to facilitate criminal investigations. The Violent Gang and Terrorist Organization File was implemented in December 1994. It is run by the National Criminal Information Center (NCIC). When the Terrorist Screening Center (TSC) became operational on