MIME(Multipurpose Internet Mail Extensions)多用途互联网邮件扩展类型。是设定某种扩展名的文件用一种应用程序来打开的方式类型,当该扩展名文件被访问的时候,浏览器会自动使 用指定应用程序来打开。多用于指定一些客户端自定义的文件名,以及一些媒体文件打开方式。
背景介绍
多用途互联网邮件扩展,它是一个互联网标准,在1992年最早应用于电子邮件系统,但后来也应用到浏览器。服务器会将它 们发送的多媒体数据的类型告诉浏览器,而通知手段就是说明该多媒体数据的MIME类型,从而让浏览器知道接收到的信息哪些是MP3文件,哪些是 Shockwave文件等等。服务器将MIME标志符放入传送的数据中来告诉浏览器使用哪种插件读取相关文件。
MIME能够支持非ASCII字符、二进制格式附件等多种格式的邮件消息。这个标准被定义在RFC 2045,RFC 2046,RFC 2047,RFC 2048,RFC 2049等RFC中。 由RFC 822转变而来的RFC 2822,规定电子邮件标准并不允许在邮件消息中使用7位ASCII字符集以外的字符。正因如此,一些非英语字符消息和二进制文件,图像,声音等非文字消息都不能在电子邮件中传输。MIME规定了用于表示各种各样的数据类型的符号化方法。
浏览器接收到文件后,会进入插件系统进行查找,查找出哪种插件可以识别读取接收到的文件。如果浏览器不清楚调用哪种插件系统,它可能会告诉用户缺少某插件,或者直接选择某现有插件来试图读取接收到的文件,或者可能会导致系统的崩溃。传输的信息中缺少MIME标识可能导致的情况很难估计,因为某些计算机系统可能不会出现什么故障,但某些计算机可能就会因此而崩溃。
Microsoft公司应用于Windows系统下的浏览器使用ActiveX控件,而不是Netscape插件,这种 浏览器不必象其它浏览器那样依靠MIME的编码。"OBJECT"标签的"CLSID"属性准确地标明了应调用哪种程序来读取接收到的文件,因此浏览器不 必象"EMBED"标签那样选择一种读取程序。正因为如此,你往往会在使用带插件的浏览器时遇到MIME问题,而使用ActiveX控件的浏览器则很少出 现此类麻烦。
正由于上述工作方式的差别也解释了一种现象,不知你是否发现在使用Netscape浏览器播放WAV文件时,浏览器会调 用LiveConnect插件进行播放,而其它浏览器一般都使用通用的QuickTime的播放插件等来进行播放,这是因为Netscape浏览器接收文 件需要读取MIME标识符,以便决定调用哪种程序来读取接收的文件,而服务器设置在Netscape浏览器中播放WAV文件应使用LiveConnect 插件,因此Netscape浏览器接收到WAV格式的文件时必然就会调用LiveConnect插件,但由于其它浏览器不使用这种方式,因此它们都使用系 统默认的播放WAV格式文件的播放器。当然Flash电影文件并不存在这种问题,因为只有Flash播放器才能够正确读取这种格式的文件。
在把输出结果传送到浏览器上的时候,浏览器必须启动适当的应用程序来处理这个输出文档。这可以通过多种类型MIME(多功能网际邮件扩充协议)来完成。在HTTP中,MIME类型被定义在Content-Type header中。
例如,假设你要传送一个Microsoft Excel文件到客户端。那么这时的MIME类型就是“excel”。在大多数实际情况中,这个文件然后将传送给Excel来处理(假设我们设定Excel为处理特殊MIME类型的应用程序)。
文件格式
最早的HTTP协议中,并没有附加的数据类型信息,所有传送的数据都被客户程序解释为超文本标记语言HTML 文档,而为了支持多媒体数据类型,HTTP协议中就使用了附加在文档之前的MIME数据类型信息来标识数据类型。
MIME意为多功能Internet邮件扩展,它设计的最初目的是为了在发送电子邮件时附加多媒体数据,让邮件客户程序能根据其类型进行处理。然而当它被HTTP协议支持之后,它的意义就更为显著了。它使得HTTP传输的不仅是普通的文本,而变得丰富多彩。
每个MIME类型由两部分组成,前面是数据的大类别,例如声音audio、图象image等,后面定义具体的种类。
常见的MIME类型(通用型):
超文本标记语言文本 .html text/html
xml文档 .xml text/xml
XHTML文档 .xhtml application/xhtml+xml
普通文本 .txt text/plain
RTF文本 .rtf application/rtf
PDF文档 .pdf application/pdf
Microsoft Word文件 .word application/msword
PNG图像 .png image/png
GIF图形 .gif image/gif
JPEG图形 .jpeg,.jpg image/jpeg
au声音文件 .au audio/basic
MIDI音乐文件 mid,.midi audio/midi,audio/x-midi
RealAudio音乐文件 .ra, .ram audio/x-pn-realaudio
MPEG文件 .mpg,.mpeg video/mpeg
AVI文件 .avi video/x-msvideo
GZIP文件 .gz application/x-gzip
TAR文件 .tar application/x-tar
任意的二进制数据 application/octet-stream
Internet中有一个专门组织IANA来确认标准的MIME类型,但Internet发展的太快,很多应用程序等不及IANA来确认他们使用的MIME类型为标准类型。因此他们使用在类别中以x-开头的方法标识这个类别还没有成为标准,例如:x-gzip,x-tar等。事实上这些类型运用的很广泛,已经成为了事实标准。只 要客户机和服务器共同承认这个MIME类型,即使它是不标准的类型也没有关系,客户程序就能根据MIME类型,采用具体的处理手段来处理数据。而Web服 务器和浏览器(包括操作系统)中,缺省都设置了标准的和常见的MIME类型,只有对于不常见的 MIME类型,才需要同时设置服务器和客户浏览器,以进行识别。
由于MIME类型与文档的后缀相关,因此服务器使用文档的后缀来区分不同文件的MIME类型,服务器中必须定义文档后缀和MIME类型之间的对应关系。而客户程序从服务器上接收数据的时候,它只是从服务器接受数据流,并不了解文档的名字,因此服务器必须使用附加信息来告诉客户程序数据的MIME类型。服务器在发送真正的数据之前,就要先发送标志数据的MIME类型的信息,这个信息使用Content-type关键字进行定义,例如对于HTML文档,服务器将首先发送以下两行MIME标识信息,这个标识并不是真正的数据文件的一部分。
Content-type: text/html
注意,第二行为一个空行,这是必须的,使用这个空行的目的是将MIME信息与真正的数据内容分隔开。
MIME利用了一个事实就是,RFC 822在消息体的内容中做了一点限制:唯一的限制就是只能使用简单的ASCII文本。所以,MIME信息由正常的Internet文本邮件组成,文本邮件 拥有一些特别的符合RFC 822的信息头和格式化过的信息体(用ASCII 的子集来表示的附件)。这些MIME头给出了一种在邮件中表示附件的特别的方法。
信息剖析
一个普通的文本邮件的信息包含一个头部分(To: From: Subject: 等等)和一个体部分(Hello Mr.,等等)。在一个符合MIME的信息中,也包含一个信息头并不奇怪,邮件的各个部分叫做MIME段,每段前也缀以一个特别的头。MIME邮件只是基 于RFC 822邮件的一个扩展,然而它有着自己的RFC规范集。
头字段
MIME头根据在邮件包中的位置,大体上分为MIME信息头和MIME段头。
MIME信息头有:
MIME-Version:
这个头提供了所用MIME的版本号。这个值习惯上为1.0。
Content-Type:
它定义了数据的类型,以便数据能被适当的处理。有效的类型 有:text,image,audio,video,applications,multipart和message。注意任何一个二进制附件都应该被叫 做application/octet- stream。这个头的一些用例为:image/jpg, application/mswork,multipart/mixed,这只是很少的一部分。
Content-Transfer-Encoding:
这是所有头中最重要的一个,因为它说明了对数据所执行的编码方式,客户/MUA 将用它对附件进行解码。对于每个附件,可以使用7bit,8bit,binary ,quoted-printable,base64和custom中的一种编码方式。7bit编码是用在US ASCII字符集上的常用的一种编码方式,也就是,保持它的原样。8bit和binary编码一般不用。对人类可读的标准文本,如果传输要经过对格式有影 响的网关时对其进行保护,可以使用quoted printable 。Base64是一种通用方法,在需要决定使用哪一种编码方法时,它提供了一个不用费脑子的选择;它通常用在二进制,非文本数据上。注意,任何非7bit 数据必须用一种模式编码,这样它就可以通过Internet邮件网关!
Content-ID:
如果Content-Type是message/external-body或multipart/alternative时,这个头就有用了,它超出了本文的范围。
Content-Description:
这是一个可选的头。它是任何信息段内容的自由文本描述。描述必须使用us-ascii码。
Content-Disposition:
一个试验性的头,它用于给客户程序/MUA提供提示,来决定是否在行内显示附件或作为单独的附件。
MIME段头(出现在实际的MIME附件部分的头),除了MIME-Version头,可以拥有以上任何头字段。如果一 个MIME头是信息块的一部分,它将作用于整个信息体。例如,如果Content-Transfer-Encoding显示在信息(指整个信息)头中,它 应用于整个信息体,但是如果它显示在一个MIME段里,它"只能"用于那个段中。
注意:其可以对自动对收到的邮件进行解密。
类型大全
格式前面为后辍名,后面为对应的MIME型(例如:rar application/x-rar-compressed 表示。RAR对应的是application/x-rar-compressed )
{ ".323", "text/h323" }, { ".3gp", "video/3gpp" }, { ".aab", "application/x-authoware-bin" }, { ".aam", "application/x-authoware-map" }, { ".aas", "application/x-authoware-seg" }, { ".acx", "application/internet-property-stream" }, { ".ai", "application/postscript" }, { ".aif", "audio/x-aiff" }, { ".aifc", "audio/x-aiff" }, { ".aiff", "audio/x-aiff" }, { ".als", "audio/X-Alpha5" }, { ".amc", "application/x-mpeg" }, { ".ani", "application/octet-stream" }, { ".apk", "application/vnd.android.package-archive" }, { ".asc", "text/plain" }, { ".asd", "application/astound" }, { ".asf", "video/x-ms-asf" }, { ".asn", "application/astound" }, { ".asp", "application/x-asap" }, { ".asr", "video/x-ms-asf" }, { ".asx", "video/x-ms-asf" }, { ".au", "audio/basic" }, { ".avb", "application/octet-stream" }, { ".avi", "video/x-msvideo" }, { ".awb", "audio/amr-wb" }, { ".axs", "application/olescript" }, { ".bas", "text/plain" }, { ".bcpio", "application/x-bcpio" }, { ".bin ", "application/octet-stream" }, { ".bld", "application/bld" }, { ".bld2", "application/bld2" }, { ".bmp", "image/bmp" }, { ".bpk", "application/octet-stream" }, { ".bz2", "application/x-bzip2" }, { ".c", "text/plain" }, { ".cal", "image/x-cals" }, { ".cat", "application/vnd.ms-pkiseccat" }, { ".ccn", "application/x-cnc" }, { ".cco", "application/x-cocoa" }, { ".cdf", "application/x-cdf" }, { ".cer", "application/x-x509-ca-cert" }, { ".cgi", "magnus-internal/cgi" }, { ".chat", "application/x-chat" }, { ".class", "application/octet-stream" }, { ".clp", "application/x-msclip" }, { ".cmx", "image/x-cmx" }, { ".co", "application/x-cult3d-object" }, { ".cod", "image/cis-cod" }, { ".conf", "text/plain" }, { ".cpio", "application/x-cpio" }, { ".cpp", "text/plain" }, { ".cpt", "application/mac-compactpro" }, { ".crd", "application/x-mscardfile" }, { ".crl", "application/pkix-crl" }, { ".crt", "application/x-x509-ca-cert" }, { ".csh", "application/x-csh" }, { ".csm", "chemical/x-csml" }, { ".csml", "chemical/x-csml" }, { ".css", "text/css" }, { ".cur", "application/octet-stream" }, { ".dcm", "x-lml/x-evm" }, { ".dcr", "application/x-director" }, { ".dcx", "image/x-dcx" }, { ".der", "application/x-x509-ca-cert" }, { ".dhtml", "text/html" }, { ".dir", "application/x-director" }, { ".dll", "application/x-msdownload" }, { ".dmg", "application/octet-stream" }, { ".dms", "application/octet-stream" }, { ".doc", "application/msword" }, { ".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document" }, { ".dot", "application/msword" }, { ".dvi", "application/x-dvi" }, { ".dwf", "drawing/x-dwf" }, { ".dwg", "application/x-autocad" }, { ".dxf", "application/x-autocad" }, { ".dxr", "application/x-director" }, { ".ebk", "application/x-expandedbook" }, { ".emb", "chemical/x-embl-dl-nucleotide" }, { ".embl", "chemical/x-embl-dl-nucleotide" }, { ".eps", "application/postscript" }, { ".epub", "application/epub+zip" }, { ".eri", "image/x-eri" }, { ".es", "audio/echospeech" }, { ".esl", "audio/echospeech" }, { ".etc", "application/x-earthtime" }, { ".etx", "text/x-setext" }, { ".evm", "x-lml/x-evm" }, { ".evy", "application/envoy" }, { ".exe", "application/octet-stream" }, { ".fh4", "image/x-freehand" }, { ".fh5", "image/x-freehand" }, { ".fhc", "image/x-freehand" }, { ".fif", "application/fractals" }, { ".flr", "x-world/x-vrml" }, { ".flv", "flv-application/octet-stream" }, { ".fm", "application/x-maker" }, { ".fpx", "image/x-fpx" }, { ".fvi", "video/isivideo" }, { ".gau", "chemical/x-gaussian-input" }, { ".gca", "application/x-gca-compressed" }, { ".gdb", "x-lml/x-gdb" }, { ".gif", "image/gif" }, { ".gps", "application/x-gps" }, { ".gtar", "application/x-gtar" }, { ".gz", "application/x-gzip" }, { ".h", "text/plain" }, { ".hdf", "application/x-hdf" }, { ".hdm", "text/x-hdml" }, { ".hdml", "text/x-hdml" }, { ".hlp", "application/winhlp" }, { ".hqx", "application/mac-binhex40" }, { ".hta", "application/hta" }, { ".htc", "text/x-component" }, { ".htm", "text/html" }, { ".html", "text/html" }, { ".hts", "text/html" }, { ".htt", "text/webviewhtml" }, { ".ice", "x-conference/x-cooltalk" }, { ".ico", "image/x-icon" }, { ".ief", "image/ief" }, { ".ifm", "image/gif" }, { ".ifs", "image/ifs" }, { ".iii", "application/x-iphone" }, { ".imy", "audio/melody" }, { ".ins", "application/x-internet-signup" }, { ".ips", "application/x-ipscript" }, { ".ipx", "application/x-ipix" }, { ".isp", "application/x-internet-signup" }, { ".it", "audio/x-mod" }, { ".itz", "audio/x-mod" }, { ".ivr", "i-world/i-vrml" }, { ".j2k", "image/j2k" }, { ".jad", "text/vnd.sun.j2me.app-descriptor" }, { ".jam", "application/x-jam" }, { ".jar", "application/java-archive" }, { ".java", "text/plain" }, { ".jfif", "image/pipeg" }, { ".jnlp", "application/x-java-jnlp-file" }, { ".jpe", "image/jpeg" }, { ".jpeg", "image/jpeg" }, { ".jpg", "image/jpeg" }, { ".jpz", "image/jpeg" }, { ".js", "application/x-javascript" }, { ".jwc", "application/jwc" }, { ".kjx", "application/x-kjx" }, { ".lak", "x-lml/x-lak" }, { ".latex", "application/x-latex" }, { ".lcc", "application/fastman" }, { ".lcl", "application/x-digitalloca" }, { ".lcr", "application/x-digitalloca" }, { ".lgh", "application/lgh" }, { ".lha", "application/octet-stream" }, { ".lml", "x-lml/x-lml" }, { ".lmlpack", "x-lml/x-lmlpack" }, { ".log", "text/plain" }, { ".lsf", "video/x-la-asf" }, { ".lsx", "video/x-la-asf" }, { ".lzh", "application/octet-stream" }, { ".m13", "application/x-msmediaview" }, { ".m14", "application/x-msmediaview" }, { ".m15", "audio/x-mod" }, { ".m3u", "audio/x-mpegurl" }, { ".m3url", "audio/x-mpegurl" }, { ".m4a", "audio/mp4a-latm" }, { ".m4b", "audio/mp4a-latm" }, { ".m4p", "audio/mp4a-latm" }, { ".m4u", "video/vnd.mpegurl" }, { ".m4v", "video/x-m4v" }, { ".ma1", "audio/ma1" }, { ".ma2", "audio/ma2" }, { ".ma3", "audio/ma3" }, { ".ma5", "audio/ma5" }, { ".man", "application/x-troff-man" }, { ".map", "magnus-internal/imagemap" }, { ".mbd", "application/mbedlet" }, { ".mct", "application/x-mascot" }, { ".mdb", "application/x-msaccess" }, { ".mdz", "audio/x-mod" }, { ".me", "application/x-troff-me" }, { ".mel", "text/x-vmel" }, { ".mht", "message/rfc822" }, { ".mhtml", "message/rfc822" }, { ".mi", "application/x-mif" }, { ".mid", "audio/mid" }, { ".midi", "audio/midi" }, { ".mif", "application/x-mif" }, { ".mil", "image/x-cals" }, { ".mio", "audio/x-mio" }, { ".mmf", "application/x-skt-lbs" }, { ".mng", "video/x-mng" }, { ".mny", "application/x-msmoney" }, { ".moc", "application/x-mocha" }, { ".mocha", "application/x-mocha" }, { ".mod", "audio/x-mod" }, { ".mof", "application/x-yumekara" }, { ".mol", "chemical/x-mdl-molfile" }, { ".mop", "chemical/x-mopac-input" }, { ".mov", "video/quicktime" }, { ".movie", "video/x-sgi-movie" }, { ".mp2", "video/mpeg" }, { ".mp3", "audio/mpeg" }, { ".mp4", "video/mp4" }, { ".mpa", "video/mpeg" }, { ".mpc", "application/vnd.mpohun.certificate" }, { ".mpe", "video/mpeg" }, { ".mpeg", "video/mpeg" }, { ".mpg", "video/mpeg" }, { ".mpg4", "video/mp4" }, { ".mpga", "audio/mpeg" }, { ".mpn", "application/vnd.mophun.application" }, { ".mpp", "application/vnd.ms-project" }, { ".mps", "application/x-mapserver" }, { ".mpv2", "video/mpeg" }, { ".mrl", "text/x-mrml" }, { ".mrm", "application/x-mrm" }, { ".ms", "application/x-troff-ms" }, { ".msg", "application/vnd.ms-outlook" }, { ".mts", "application/metastream" }, { ".mtx", "application/metastream" }, { ".mtz", "application/metastream" }, { ".mvb", "application/x-msmediaview" }, { ".mzv", "application/metastream" }, { ".nar", "application/zip" }, { ".nbmp", "image/nbmp" }, { ".nc", "application/x-netcdf" }, { ".ndb", "x-lml/x-ndb" }, { ".ndwn", "application/ndwn" }, { ".nif", "application/x-nif" }, { ".nmz", "application/x-scream" }, { ".nokia-op-logo", "image/vnd.nok-oplogo-color" }, { ".npx", "application/x-netfpx" }, { ".nsnd", "audio/nsnd" }, { ".nva", "application/x-neva1" }, { ".nws", "message/rfc822" }, { ".oda", "application/oda" }, { ".ogg", "audio/ogg" }, { ".oom", "application/x-AtlasMate-Plugin" }, { ".p10", "application/pkcs10" }, { ".p12", "application/x-pkcs12" }, { ".p7b", "application/x-pkcs7-certificates" }, { ".p7c", "application/x-pkcs7-mime" }, { ".p7m", "application/x-pkcs7-mime" }, { ".p7r", "application/x-pkcs7-certreqresp" }, { ".p7s", "application/x-pkcs7-signature" }, { ".pac", "audio/x-pac" }, { ".pae", "audio/x-epac" }, { ".pan", "application/x-pan" }, { ".pbm", "image/x-portable-bitmap" }, { ".pcx", "image/x-pcx" }, { ".pda", "image/x-pda" }, { ".pdb", "chemical/x-pdb" }, { ".pdf", "application/pdf" }, { ".pfr", "application/font-tdpfr" }, { ".pfx", "application/x-pkcs12" }, { ".pgm", "image/x-portable-graymap" }, { ".pict", "image/x-pict" }, { ".pko", "application/ynd.ms-pkipko" }, { ".pm", "application/x-perl" }, { ".pma", "application/x-perfmon" }, { ".pmc", "application/x-perfmon" }, { ".pmd", "application/x-pmd" }, { ".pml", "application/x-perfmon" }, { ".pmr", "application/x-perfmon" }, { ".pmw", "application/x-perfmon" }, { ".png", "image/png" }, { ".pnm", "image/x-portable-anymap" }, { ".pnz", "image/png" }, { ".pot,", "application/vnd.ms-powerpoint" }, { ".ppm", "image/x-portable-pixmap" }, { ".pps", "application/vnd.ms-powerpoint" }, { ".ppt", "application/vnd.ms-powerpoint" }, { ".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation" }, { ".pqf", "application/x-cprplayer" }, { ".pqi", "application/cprplayer" }, { ".prc", "application/x-prc" }, { ".prf", "application/pics-rules" }, { ".prop", "text/plain" }, { ".proxy", "application/x-ns-proxy-autoconfig" }, { ".ps", "application/postscript" }, { ".ptlk", "application/listenup" }, { ".pub", "application/x-mspublisher" }, { ".pvx", "video/x-pv-pvx" }, { ".qcp", "audio/vnd.qcelp" }, { ".qt", "video/quicktime" }, { ".qti", "image/x-quicktime" }, { ".qtif", "image/x-quicktime" }, { ".r3t", "text/vnd.rn-realtext3d" }, { ".ra", "audio/x-pn-realaudio" }, { ".ram", "audio/x-pn-realaudio" }, { ".rar", "application/octet-stream" }, { ".ras", "image/x-cmu-raster" }, { ".rc", "text/plain" }, { ".rdf", "application/rdf+xml" }, { ".rf", "image/vnd.rn-realflash" }, { ".rgb", "image/x-rgb" }, { ".rlf", "application/x-richlink" }, { ".rm", "audio/x-pn-realaudio" }, { ".rmf", "audio/x-rmf" }, { ".rmi", "audio/mid" }, { ".rmm", "audio/x-pn-realaudio" }, { ".rmvb", "audio/x-pn-realaudio" }, { ".rnx", "application/vnd.rn-realplayer" }, { ".roff", "application/x-troff" }, { ".rp", "image/vnd.rn-realpix" }, { ".rpm", "audio/x-pn-realaudio-plugin" }, { ".rt", "text/vnd.rn-realtext" }, { ".rte", "x-lml/x-gps" }, { ".rtf", "application/rtf" }, { ".rtg", "application/metastream" }, { ".rtx", "text/richtext" }, { ".rv", "video/vnd.rn-realvideo" }, { ".rwc", "application/x-rogerwilco" }, { ".s3m", "audio/x-mod" }, { ".s3z", "audio/x-mod" }, { ".sca", "application/x-supercard" }, { ".scd", "application/x-msschedule" }, { ".sct", "text/scriptlet" }, { ".sdf", "application/e-score" }, { ".sea", "application/x-stuffit" }, { ".setpay", "application/set-payment-initiation" }, { ".setreg", "application/set-registration-initiation" }, { ".sgm", "text/x-sgml" }, { ".sgml", "text/x-sgml" }, { ".sh", "application/x-sh" }, { ".shar", "application/x-shar" }, { ".shtml", "magnus-internal/parsed-html" }, { ".shw", "application/presentations" }, { ".si6", "image/si6" }, { ".si7", "image/vnd.stiwap.sis" }, { ".si9", "image/vnd.lgtwap.sis" }, { ".sis", "application/vnd.symbian.install" }, { ".sit", "application/x-stuffit" }, { ".skd", "application/x-Koan" }, { ".skm", "application/x-Koan" }, { ".skp", "application/x-Koan" }, { ".skt", "application/x-Koan" }, { ".slc", "application/x-salsa" }, { ".smd", "audio/x-smd" }, { ".smi", "application/smil" }, { ".smil", "application/smil" }, { ".smp", "application/studiom" }, { ".smz", "audio/x-smd" }, { ".snd", "audio/basic" }, { ".spc", "application/x-pkcs7-certificates" }, { ".spl", "application/futuresplash" }, { ".spr", "application/x-sprite" }, { ".sprite", "application/x-sprite" }, { ".sdp", "application/sdp" }, { ".spt", "application/x-spt" }, { ".src", "application/x-wais-source" }, { ".sst", "application/vnd.ms-pkicertstore" }, { ".stk", "application/hyperstudio" }, { ".stl", "application/vnd.ms-pkistl" }, { ".stm", "text/html" }, { ".svg", "image/svg+xml" }, { ".sv4cpio", "application/x-sv4cpio" }, { ".sv4crc", "application/x-sv4crc" }, { ".svf", "image/vnd" }, { ".svg", "image/svg+xml" }, { ".svh", "image/svh" }, { ".svr", "x-world/x-svr" }, { ".swf", "application/x-shockwave-flash" }, { ".swfl", "application/x-shockwave-flash" }, { ".t", "application/x-troff" }, { ".tad", "application/octet-stream" }, { ".talk", "text/x-speech" }, { ".tar", "application/x-tar" }, { ".taz", "application/x-tar" }, { ".tbp", "application/x-timbuktu" }, { ".tbt", "application/x-timbuktu" }, { ".tcl", "application/x-tcl" }, { ".tex", "application/x-tex" }, { ".texi", "application/x-texinfo" }, { ".texinfo", "application/x-texinfo" }, { ".tgz", "application/x-compressed" }, { ".thm", "application/vnd.eri.thm" }, { ".tif", "image/tiff" }, { ".tiff", "image/tiff" }, { ".tki", "application/x-tkined" }, { ".tkined", "application/x-tkined" }, { ".toc", "application/toc" }, { ".toy", "image/toy" }, { ".tr", "application/x-troff" }, { ".trk", "x-lml/x-gps" }, { ".trm", "application/x-msterminal" }, { ".tsi", "audio/tsplayer" }, { ".tsp", "application/dsptype" }, { ".tsv", "text/tab-separated-values" }, { ".ttf", "application/octet-stream" }, { ".ttz", "application/t-time" }, { ".txt", "text/plain" }, { ".uls", "text/iuls" }, { ".ult", "audio/x-mod" }, { ".ustar", "application/x-ustar" }, { ".uu", "application/x-uuencode" }, { ".uue", "application/x-uuencode" }, { ".vcd", "application/x-cdlink" }, { ".vcf", "text/x-vcard" }, { ".vdo", "video/vdo" }, { ".vib", "audio/vib" }, { ".viv", "video/vivo" }, { ".vivo", "video/vivo" }, { ".vmd", "application/vocaltec-media-desc" }, { ".vmf", "application/vocaltec-media-file" }, { ".vmi", "application/x-dreamcast-vms-info" }, { ".vms", "application/x-dreamcast-vms" }, { ".vox", "audio/voxware" }, { ".vqe", "audio/x-twinvq-plugin" }, { ".vqf", "audio/x-twinvq" }, { ".vql", "audio/x-twinvq" }, { ".vre", "x-world/x-vream" }, { ".vrml", "x-world/x-vrml" }, { ".vrt", "x-world/x-vrt" }, { ".vrw", "x-world/x-vream" }, { ".vts", "workbook/formulaone" }, { ".wav", "audio/x-wav" }, { ".wax", "audio/x-ms-wax" }, { ".wbmp", "image/vnd.wap.wbmp" }, { ".wcm", "application/vnd.ms-works" }, { ".wdb", "application/vnd.ms-works" }, { ".web", "application/vnd.xara" }, { ".wi", "image/wavelet" }, { ".wis", "application/x-InstallShield" }, { ".wks", "application/vnd.ms-works" }, { ".wm", "video/x-ms-wm" }, { ".wma", "audio/x-ms-wma" }, { ".wmd", "application/x-ms-wmd" }, { ".wmf", "application/x-msmetafile" }, { ".wml", "text/vnd.wap.wml" }, { ".wmlc", "application/vnd.wap.wmlc" }, { ".wmls", "text/vnd.wap.wmlscript" }, { ".wmlsc", "application/vnd.wap.wmlscriptc" }, { ".wmlscript", "text/vnd.wap.wmlscript" }, { ".wmv", "audio/x-ms-wmv" }, { ".wmx", "video/x-ms-wmx" }, { ".wmz", "application/x-ms-wmz" }, { ".wpng", "image/x-up-wpng" }, { ".wps", "application/vnd.ms-works" }, { ".wpt", "x-lml/x-gps" }, { ".wri", "application/x-mswrite" }, { ".wrl", "x-world/x-vrml" }, { ".wrz", "x-world/x-vrml" }, { ".ws", "text/vnd.wap.wmlscript" }, { ".wsc", "application/vnd.wap.wmlscriptc" }, { ".wv", "video/wavelet" }, { ".wvx", "video/x-ms-wvx" }, { ".wxl", "application/x-wxl" }, { ".x-gzip", "application/x-gzip" }, { ".xaf", "x-world/x-vrml" }, { ".xar", "application/vnd.xara" }, { ".xbm", "image/x-xbitmap" }, { ".xdm", "application/x-xdma" }, { ".xdma", "application/x-xdma" }, { ".xdw", "application/vnd.fujixerox.docuworks" }, { ".xht", "application/xhtml+xml" }, { ".xhtm", "application/xhtml+xml" }, { ".xhtml", "application/xhtml+xml" }, { ".xla", "application/vnd.ms-excel" }, { ".xlc", "application/vnd.ms-excel" }, { ".xll", "application/x-excel" }, { ".xlm", "application/vnd.ms-excel" }, { ".xls", "application/vnd.ms-excel" }, { ".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" }, { ".xlt", "application/vnd.ms-excel" }, { ".xlw", "application/vnd.ms-excel" }, { ".xm", "audio/x-mod" }, { ".xml", "text/plain" }, { ".xmz", "audio/x-mod" }, { ".xof", "x-world/x-vrml" }, { ".xpi", "application/x-xpinstall" }, { ".xpm", "image/x-xpixmap" }, { ".xsit", "text/xml" }, { ".xsl", "text/xml" }, { ".xul", "text/xul" }, { ".xwd", "image/x-xwindowdump" }, { ".xyz", "chemical/x-pdb" }, { ".yz1", "application/x-yz1" }, { ".z", "application/x-compress" }, { ".zac", "application/x-zaurus-zac" }, { ".zip", "application/zip" }, { ".json", "application/json" },