Hi monks

Could any of the esteemed monks could explain this regex. This regex is used to get swf files from html pages.
The regex is m/\.swf(?:\?.*)?$/oi. I am not understanding the meaning thing inside the brackets. Why is "?" used in the regex. After some searching in google i feel "?:" is optional kind of thing. Thanks in advance.

Regards
Kiran.

In reply to questions of a perl beginner on regex by jithoosin

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