Everyone claims to be someone else. The historical change of--http agreement useragent

Google Chrome has made everyone hot, and only professional users will notice the "mozilla/5.0 Windows" that are issued when Chrome accesses the Web page. U Windows NT 5.1; En-US) applewebkit/525.13 (khtml, like Gecko) chrome/0.2.149.27 safari/525.13 "useragent string, seemingly heavenly book, what is it exactly what it represents." Let's take a look.

The earliest time there was a browser called NCSA Mosaic, labeled as ncsa_mosaic/2.0 (Windows 3.1), which supported the text display while also supporting the picture, so the web began to be fun.

Then appeared a new Web browser, "Mozilla", in fact, is "mosaic Terminator" meaning, this make mosaic very uncomfortable, (after all Mosaic debut early, lake Old), the new browser finally officially announced the name is Netscape, It labeled itself as mozilla/1.0 (Win3.1), which was even more fun. The Netscape Support framework shows that later, the framework is popular among us, but Mosaic does not support the framework ah, so the great "user agent Detection" technology appears, if it is "Mozilla", it is sent to support the framework of the page, as for other browsers, the page is sent without frames.

Netscape wanted to tease Microsoft and call Windows "a device drive that has barely been debugged," and the latter annoyed. Microsoft has launched its own web browser, called Internet Explorer, in the hope that it will become the "Netscape Terminator". Internet Explorer also supports the framework, but it's not Mozilla, so no one is sending it a frames page. Microsoft slowly became agitated, and no longer wanted the webmaster to get to know IE and give it a frame, but instead claimed to be "compatible with Mozilla" and began imitating Netscape, calling itself mozilla/1.22 (compatible; MSIE 2.0; Windows 95) so that Internet Explorer can also receive the framework, the entire Microsoft Ecstasy, but webmasters are starting to get a little confused.

Microsoft sold IE and Windows together and made the product better than Netscape, and opened the first browser battle. As you know, Netscape was killed, and Microsoft was a big win. But later, Netscape was reborn as Mozilla's new name, and constructed gecko, a nominal mozilla/5.0 (Windows; U Windows NT 5.0; En-us; rv:1.1) Gecko/20020826,gecko belongs to the rendering engine and has excellent performance. Mozilla developed Firefox, labeled mozilla/5.0 (Windows; U Windows NT 5.1; Sv-se; rv:1.7.5) gecko/20041108 firefox/1.0, and Firefox is also a very good performance. Gecko expands rapidly, some browsers use its code and label it as mozilla/5.0 (Macintosh; U PPC Mac OS X mach-o; En-us; rv:1.7.2) gecko/20040825 camino/0.8.1, which is one, and mozilla/5.0 (Windows; U Windows NT 5.1; De rv:1.8.1.8) gecko/20071008 seamonkey/1.0, another, they are all disguised as Mozilla, but also based on Gecko support.

Gecko performance is excellent, ie is very poor, so identity screening occurs again, conveying to Gecko is a well-designed Web page code, other browsers do not have this treatment. Linux followers are sad because they create konqueror based on the khtml engine, but they don't get the code, though they think khtml is as good as gecko, so konquerer starts pretending to be "like Gecko." So to get good web pages, and nominal themselves as mozilla/5.0 (compatible; konqueror/3.2; FreeBSD) (khtml, like Gecko), the world is even more confusing.

MM Small Game

Later appeared opera such as, claiming that "allow the user to make their own decision to install the browser", its menu provides mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; EN) Opera 9.51, mozilla/5.0 (Windows NT 6.0; U En rv:1.8.1) gecko/20061208 firefox/2.0.0 Opera 9.51,opera/9.51 (Windows NT 5.1; U EN) for everyone to choose, who to choose.

Apple has developed safari, used khtml, but also added a lot of new features, and then simply Shi, and then started to call WebKit, but it has the hope of getting those pages written for khtml, so safari nominal himself as mozilla/5.0 ( Macintosh; U PPC Mac OS X; De-de) applewebkit/85.7 (khtml, like Gecko) safari/85.5, the world is more chaotic.

Microsoft is increasingly worried about the development of Firefox, restart the development of Internet Explorer, nominal itself as mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0), it's good to render code, but that depends on whether the webmaster instructs it to do so.

Beautiful little Game

Google has also developed its own browser Chrome, using WebKit, a bit like safari, hoping to get a Web page for Safari, and decided to put it on safari. In this way, Chrome uses the WebKit rendering engine, wants to pretend to be safari, and WebKit is pretending to be khtml,khtml and pretending to be gecko, and all browsers claim to be Mozilla, so Chrome claims itself to be mozilla/5.0 (Windows; U Windows NT 5.1; En-US) applewebkit/525.13 (khtml, like Gecko) chrome/0.2.149.27 safari/525.13,,useragent string is completely confusing and almost no longer works, Everyone claims to be someone else, and chaos fills the world.