A print widget for the esri js api.
var printWidget = new Print({
map: map,
printTaskURL: "https://utility.arcgisonline.com/arcgis/rest/services/Utilities/PrintingTools/GPServer/Export%20Web%20Map%20Task",
authorText: "Dave",
copyrightText: "2014",
defaultTitle: "My Map",
defaultFormat: "PDF",
defaultLayout: null
}, 'printDijit');
printWidget.startup();
Screen from Sample page: