1. A non-transitory computer-readable information recording medium comprising a plugin program that when read by a client device, causes the client device to: extract, from a Web document being displayed within a browser display window on a screen, text contained within a region of the Web document which is specified by a user moving a mouse cursor over the text; in response to the extracting, send queries having said text to at least three servers previously registered by the user in the plugin program; receive, in response to the queries, information from each of the at least three servers; generate a popup window for each of the received information, wherein the information from each respective server of the at least three servers is associated with a different popup window; display one of the generated popup windows corresponding to first arrived information of the information received from the at least three servers on the screen in front of a portion of said Web document; display each of the generated popup windows corresponding to later arriving information from the at least three servers on the screen so that each said generated popup window is displayed shifted and stacked behind any of the generated popup windows already displayed on the screen, wherein a title portion of each of said generated popup windows is visible on the screen; receive user input that specifies the title portion of one of the displayed popup windows which is shifted and stacked behind other displayed popup windows; and responsive to the user input, move the displayed popup window associated with the specified title portion in front of all of the other popup windows already displayed on the screen.