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In some situation we have to detect the browser and perform the different operations on different ones. If we talk about the WordPress then there are many global variables available to detect the browser on which you are processing the website. We are going to list the global variables.

A) $is_iphone : Its name indicating that it is for safri in iphone.

B) $is_safari : It is useful to detect the safari browser.

C) $is_NS4 : Helpful to deect the netscape4.

D) $is_chrome : for google chrome detection.

E) $is_winIE : for windows internet explorer.

F) $is_macIE : for mac internet explorer.

G) $is_opera : for opera.

F) $is_gecko : for firefox.

H) $is_IE : for internet explorer.

These variables include Boolean value, true or false. These by-default value is false. It will be become true when page loads in selected one. It is most easiest way to manage the different operations on different browsers.