Multinational Character Set is a character encoding created by Digital Equipment Corporation for use in the popular VT220 terminal. It was an 8-bit extension of ASCII that added accented characters, currency symbols, and other things missing from 7-bit ASCII.

Such "extended ASCII" sets were common, but MCS has the distinction of being the ancestor of both ISO 8859-1 and Unicode. If you compare the code chart of MCS with ISO 8859-1 or the first 256 code points of Unicode, you will see that they have many more similarities than differences.

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