PHP is a server-side scripting language used to develop applications on the Web. Browsers interpret PHP code and pages with the PHP file extension in the same way they do HTML Web programming lanuage files, so you won't notice any difference between the two online. If you download a PHP file to your computer, Windows may not recognize the PHP extension and tell you it can't open the file. However, PHP is usually written using a Web design program or a basic text editor, and you may use any of these to open PHP files. Windows Notepad is a free tool for this.
Click the Windows orb, and then type "Notepad" into the search box and press "Enter." Click "Notepad" in the results list to open the application.
Click "File" from the Notepad menu and then click "Open." This brings up a dialog box with your system files.
Navigate through your system files to the PHP file you want to open. Click the file and then click the "Open" button, or just double-click the file to open it in Notepad.