A network system includes a client for browsing a web page, a conversion server for providing a function for performing a predetermined process for the web page, and a web server for storing the web page that includes a function button used to request that a process be performed by the conversion server, wherein the client obtains the web page and selects the function button, the client designates the storage location for the target web page and transmits a process execution request to the conversion server, wherein the conversion server obtains the target web page based on the storage location that is designated by the process execution request, performs a pertinent process for the target web page that is obtained, and returns the resultant web page to the client that issued the process execution request.