The second group of characters, from 128 through 255, in the ASCII character set. The extended ASCII character set is assigned variable sets of characters by computer hardware manufacturers and software developers, and it is not necessarily compatible between different computers. The IBM extended character set used in the PC (see Appendix C) includes mathematics symbols and characters from the PC line-drawing set.
See also American Standard Code for Information Interchange; ASCII file; ASCII standard character set; double-byte character set; Extended Binary Coded Decimal Interchange Code; Unicode.