public static CharSequence drop(int num)What this method do is the opposite of take. Take returns the first num characters. But this method removes them! So it returns the String without the first num characters.
See below example on how to use the drop method of Groovy String.
def text = "abcd" println text.drop( 2 )
We have the String abcd and we remove the first 2 characters. So we get
cdPretty simple and straight forward. Gotta love Groovy!