Run a script on my webserver when I click a button on the webpage on a remote machine

I want to be able to have a button on a webpage hosted on webserver x, and then have it so when button y is clicked by a remote user on webpage z, which is on server x, a script on server x will run on server x. Also if possible I want to have a text input that will be used by the script as input. I cant find anything similar to this and dont know how to go about figuringit out myself. If you know how to do this please reply. Thanks