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  36 <TR><TD><A href="http://sourceforge.net/projects/sevenzip/"><B>SourceForge</B></A></TD></TR>\r
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  40 \r
  41 <P>\r
  42 <B>English</B><BR>\r
  43 <A href="http://7zip.usb-drivers.org/">Afrikaans</A><BR>\r
  44 <A href="http://7zip-ar.com/">Arabic</A><BR>\r
  45 <A href="http://7-zip.hit.bg/">Bulgarian</A><BR>\r
  46 <A href="http://sparanoid.com/lab/7z/">Chinese Simpl.</A><BR>\r
  47 <A href="http://www.developershome.com/7-zip/">Chinese Trad.</A><BR>\r
  48 <A href="http://7zip-eo.rnbastos.com/">Esperanto</A><BR>\r
  49 <A href="http://www.spiroo.be/7zip/">French</A><BR>\r
  50 <A href="http://www.7-zip.de/">German</A><BR>\r
  51 <A href="http://7-zip.hu/">Hungarian</A><BR>\r
  52 <A href="http://sevenzip.sourceforge.jp/">Japanese</A><BR>\r
  53 <A href="http://7-zip.ir/">Persian</A><BR>\r
  54 <A href="http://7-zip.org.pl/">Polish</A><BR>\r
  55 <A href="http://7zip.rnbastos.com/">Portuguese Brazil</A><BR>\r
  56 <A href="http://7-zip.org.ua/ru/">Russian</A><BR>\r
  57 <A href="http://7-zip.com.mx">Spanish</A><BR>\r
  58 <A href="http://7zip-thai.inetbridge.net/">Thai</A><BR>\r
  59 <A href="http://7-zip.org.ua/">Ukrainian</A><BR>\r
  60 <A href="http://7zip-vi.updatestar.com/">Vietnamese</A><BR>\r
  61 </P>\r
  62 \r
  63           \r
  64 </TD>\r
  65 <TD valign="top">\r
  66 \r
  67 <H1>7z Format</H1>\r
  68 \r
  69 <P><B>7z</B> is the new archive format, providing high compression ratio.</P>\r
  70 \r
  71 <P>The main features of <B>7z</B> format:</P>\r
  72 <UL>\r
  73   <LI>Open architecture\r
  74   <LI>High compression ratio\r
  75   <LI>Strong AES-256 encryption\r
  76   <LI>Ability of using any compression, conversion or encryption method\r
  77   <LI>Supporting files with sizes up to 16000000000 GB\r
  78   <LI>Unicode file names\r
  79   <LI>Solid compressing\r
  80   <LI>Archive headers compressing\r
  81 </UL>\r
  82 \r
  83 <P><B>7z</B> has open architecture, so it can support any new compression methods.\r
  84 Now the following methods are integrated to <B>7z</B>:</P>\r
  85 \r
  86 <TABLE cellspacing ="2" cellpadding ="4">\r
  87   <TR> <TH class="Title" width="60">Method</TH> <TH class="Title">Description</TH></TR>\r
  88   <TR> <TD class="Item">LZMA</TD> <TD class="Item">Improved and optimized version of LZ77 algorithm</TD></TR>\r
  89   <TR> <TD class="Item">LZMA2</TD> <TD class="Item">Improved version of LZMA</TD></TR>\r
  90   <TR> <TD class="Item">PPMD</TD> <TD class="Item">Dmitry Shkarin's PPMdH with small changes</TD></TR>\r
  91   <TR> <TD class="Item">BCJ</TD> <TD class="Item">Converter for 32-bit x86 executables</TD></TR>\r
  92   <TR> <TD class="Item">BCJ2</TD> <TD class="Item">Converter for 32-bit x86 executables</TD></TR>\r
  93   <TR> <TD class="Item">BZip2</TD> <TD class="Item">Standard BWT algorithm</TD></TR>\r
  94   <TR> <TD class="Item">Deflate</TD> <TD class="Item">Standard LZ77-based algorithm</TD></TR>\r
  95 </TABLE>\r
  96 \r
  97 <P><B>LZMA</B> is default and general compression method of <B>7z</B> format. The main features of <B>LZMA</B> method:</P>\r
  98 <UL>\r
  99   <LI>High compression ratio\r
 100   <LI>Variable dictionary size (up to 4 GB)\r
 101   <LI>Compressing speed: about 1 MB/s on 2 GHz CPU\r
 102   <LI>Decompressing speed: about 10-20 MB/s on 2 GHz CPU\r
 103   <LI>Small memory requirements for decompressing (depend from dictionary size)\r
 104   <LI>Small code size for decompressing: about 5 KB\r
 105   <LI>Supporting multi-threading and P4's hyper-threading\r
 106 </UL>\r
 107 \r
 108 <P><B>LZMA</B> compression algorithm is very suitable for embedded applications.\r
 109 <B>LZMA</B> is released under the terms of the GNU LGPL. <B>LZMA</B> is also \r
 110 available under a proprietary license for those who can not use the GNU LGPL in \r
 111 their code. If you want to use <B>LZMA</B> code, you can ask consultations, \r
 112 custom code programming and required developer licenses \r
 113 from page for support:\r
 114 <A href="support.html">Send message to LZMA developer</A>.\r
 115 Check also information about <A href ="sdk.html">LZMA SDK</A>.</P>\r
 116 \r
 117 <P>7-Zip also supports encryption with AES-256 algorithm. \r
 118 This algorithm uses cipher key with length of 256 bits. To create that key 7-Zip \r
 119 uses derivation function based on SHA-256 hash algorithm.\r
 120 A key derivation function produces a derived key from text password defined by user.\r
 121 For increasing the cost of exhaustive search for passwords 7-Zip uses big number \r
 122 of iterations to produce cipher key from text password.</P>\r
 123 \r
 124 <P><B>7z</B> is a part of <A href="./">7-Zip</A> program distributed under the GNU LGPL. \r
 125 You can download <B>7-Zip</B> sources and binaries from <A href ="download.html">Download Page</A>.</P>\r
 126 \r
 127 <p>Applications that support <B>7z</B> archives: WinRAR, PowerArchiver, TUGZip, IZArc.</p>\r
 128 \r
 129 <p>Links:</p>\r
 130 <ul>\r
 131 <li><A href="http://en.wikipedia.org/wiki/7z">7z at Wikipedia</A></li>\r
 132 </ul>\r
 133 \r
 134 \r
 135 <HR>\r
 136 <P><SMALL>Copyright (C) 2014 Igor Pavlov.</SMALL></P>\r
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