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<html xmlns="http://www.w3.org/1999/xhtml"><head><title>meta bit</title><link rel="stylesheet" href="../../jargon.css" type="text/css"/><meta name="generator" content="DocBook XSL Stylesheets V1.61.0"/><link rel="home" href="../index.html" title="The Jargon File"/><link rel="up" href="../M.html" title="M"/><link rel="previous" href="meta.html" title="meta"/><link rel="next" href="metasyntactic-variable.html" title="metasyntactic variable"/></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">meta bit</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="meta.html">Prev</a> </td><th width="60%" align="center">M</th><td width="20%" align="right"> <a accesskey="n" href="metasyntactic-variable.html">Next</a></td></tr></table><hr/></div><dt><a id="meta-bit"/><dt xmlns="" id="meta-bit"><b>meta bit</b>: <span xmlns="http://www.w3.org/1999/xhtml" class="grammar">n.</span></dt></dt><dd><p> The top bit of an 8-bit character, which is on in character values
128--255. Also called <a href="../H/high-bit.html"><i class="glossterm">high bit</i></a>,
<a href="../A/alt-bit.html"><i class="glossterm">alt bit</i></a>. Some terminals and consoles (see
<a href="../S/space-cadet-keyboard.html"><i class="glossterm">space-cadet keyboard</i></a>) have a META shift key. Others (including,
<span class="emphasis"><em>mirabile dictu</em></span>, keyboards on IBM PC-class machines)
have an ALT key. See also <a href="../B/bucky-bits.html"><i class="glossterm">bucky bits</i></a>.</p><p>Historical note: although in modern usage shaped by a universe of
8-bit bytes the meta bit is invariably hex 80 (octal 0200), things were
different on earlier machines with 36-bit words and 9-bit bytes. The MIT
and Stanford keyboards (see <a href="../S/space-cadet-keyboard.html"><i class="glossterm">space-cadet keyboard</i></a>)
generated hex 100 (octal 400) from their meta keys.</p></dd><div class="navfooter"><hr/><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="meta.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="../M.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="metasyntactic-variable.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">meta </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> metasyntactic variable</td></tr></table></div></body></html>