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In computing, solid compression refers to a method for data compression of multiple files, wherein all the uncompressed files are concatenated and treated as a single data block. Such an archive is called a solid archive. It is used natively in the 7z 〔(【引用サイトリンク】title=7za man page )〕 and RAR 〔(【引用サイトリンク】url=http://pot-pourri.fltr.ucl.ac.be/files/ARCH/RAR_FAQ.TXT )〕 formats, as well as indirectly in tar-based formats such as .tar.gz and .tar.bz2. By contrast, the ZIP format is not solid because it stores separate compressed files (though solid compression can be emulated for small archives by combining the files into an uncompressed zip archive and then compressing the zip archive inside a second compressed zip file).〔http://cafxx.strayorange.com/Emulate%20solid%20archiving%20with%20ZIP〕〔http://www.pcreview.co.uk/forums/zip-and-solid-archives-t2476437.html〕==Explanation== Compressed file formats often feature both compression (storing the data in a small space) and archiving (storing multiple files and metadata in a single file). One can combine these in two natural ways: * compress the individual files, and then archive into a single file; * archive into a single data block, and then compress. The order matters (these operations do not commute), and the latter is solid compression. In Unix, compression and archiving are traditionally separate operations, which allows one to understand this distinction: * compressing individual files and then archiving would be a tar ''of'' gzip'ed files – this is very uncommon, while* archiving via tar and ''then'' compressing yields a compressed archive: a .tar.gz – and this is solid compression.抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「solid compression」の詳細全文を読む スポンサード リンク
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