Clicking on Pop-ups is not always safe.

It is not safe to click on pop-ups, doing so your computer might get infected with ad-wares or spyware's. Remember, no trusted site's will show pop-ups. To safely close Pop-ups highlight the popup by clicking on the taskbar and then press Alt+F4, if this does not work, open task manager and in the applications tab right click on the pop-up window and then "Go To Process" this will highlight the process of the popup window, now end this process.