Javascript window.open() method will pop up a new window. window.write() method can be used to write into to the page.

var w = window.open("","endmemo","width=500, height=80");
w.document.write("EndMemo.com javascript Tutorial");

Be sure that the new window is not blocked by your browser.

To open a specified URL:

window.open("index.php");

window.open(url,name,specs,replace)
url: the url to open. if it is empty, then open a new window
name: the new window name. _blank: new window; _parent: load into the parent frame; _self: replace current page;
specs: window parameters, include height, width, left, top with pixel values; and location, menubar, resizeable, scrollbars, status, titlebar, toolbar with yes or no values
replace: true: replace current document in the history list; creates new entry in the history list