VARIOUS CHARACTER SETS are used on OpenVMS systems, including Unicode, ISO Latin-1, ASCII, the DEC Multinational Character Set (MCS), and the DEC Technical Character Set.

The specific character sets used for your applications will depend on which characters you need to display, and which characters can be displayed on your terminals and terminal emulators. Most applications will use the Latin-1 and the MCS character sets.

The Latin-1 and MCS character sets are closely related, and both are effectively extensions to the ASCII character set. In Latin-1, MCS, and ASCII, each character consists of 1 byte of data, 8 bits. Traditional ASCII applications use 7 of these bits in each byte. All 128 characters available in 7-bit ASCII have been assigned. Latin-1 and MCS have additional characters, characters assigned 8-bit values. One 7-bit ASCII character you will see through this book is the escape character, with an ASCII value of 27.

New characters are assigned or reassigned within the Latin-1 character set on occasion. Among the newer characters is the Euro currency character. These newer characters may or many not be displayed by your terminals.

The Latin-1 and MCS character sets provide the majority of the characters necessary for Romance languages. Most current terminals and the DECwindows DECterm terminal emulator use the ISO Latin-1 character set. Other terminals and terminal emulators use the DEC MCS or ASCII character sets. These are the character sets that you will be using with most DCL applications and with most terminals.

Unicode uses multiple bytes...