Class 5 Keypoint: Using GetUrlVar to get variables from other HTML file pages. Page A can open Page B with variables as input for page B, so page B can show different content for each input. For this we use the following function inside page B: function GetUrlVar ( VarName) { name = name . replace ( / [ \[ ] / , "\\\[" ) . replace ( / [ \] ] / , "\\\]" ) ; var regexS = "[\\?&]" + VarName + "=([^&#]*)" ; var regex = new RegExp ( regexS ) ; var results = regex . exec ( window . location . href ) ; if ( results == null ) return "" ; else return results [ 1 ] ; } var filmid = decodeURIComponent ( GetUrlVar ( 'filmid' ) ) ; var numID = Number ( filmid ) ; document . getElementById ( "demo" ) . innerHTML = writeText ( numID ) ; Where filmid is the variable to store variable from URL, but it is saved as char string, to cast to integer we create numID and cast to an integer...