How PHP makes Office documents and PDF files appear directly on a Web page

How does PHP make Office documents and PDF files appear directly on a Web page?
displayed directly in the Web page, and the arrangement of those are all right, as shown with the client open!
I use the link, under the Mac, with Safari this browser can be directly displayed to the Web page, but under Windows with IE Access when prompted to open or save, open directly on the client opened!
I want to click on the direct display to the page, how can this be achieved?

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In fact, the following Chrome can be opened directly, which is related to the browser, such as IE, the old guy estimated to have to install the plug-in what?
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The browser can only open files it can recognize, if a download dialog box appears, the browser does not recognize him
You need to install the appropriate program or plugin
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Explore

The browser can only open files it can recognize, if a download dialog box appears, the browser does not recognize him
You need to install the appropriate program or plugin

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If you want to unify the performance of all browsers, there is only one way to convert these files to HTML format on the server side.

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