Hello shankonit,

If you have access to the Camel Book (4^th Edition, 2012), you should look at Chapter 5, “Pattern Matching,” especially the section “The Little Engine That /Could(n’t)?/” (pages 241–6). Rule 5 covers the behaviour of quantifiers; the final two paragraphs nicely explain the difference between greedy and non-greedy matching in terms of “backward” vs. “forward” backtracking.

Note for pedants: Messrs Christiansen, d foy, Wall, and Orwant use the term frugal as a synonym for non-greedy. :-)

Hope that helps,