I am new in this forum so i want to know about this forum, please help me to know this forum well.
Hi shakil2389 and welcome to the forums. 
Surely you must have thought the forum was important in some way, or you wouldn’t have bothered to join, so I don’t think I need to answer that.
If you’re looking for help on how the forum works, then you can find that here: http://www.sitepoint.com/forums/faq.php?faq=vb3_board_faq#faq_vb3_board_usage
and the forum rules/FAQs are here: http://www.sitepoint.com/forums/faq.php
I am new here.
Hi shuvro905 - you’re welcome here, too.
Suddenly, this seems to be a very popular question, so I’ve merged your post into this thread.
A forum is a place on the internet where people can ask their questions and start discussion with other registered members/users.
I was searching up forums within my interest and I found this one and got signed up
Well forums are for people with similar interests to discuss topics related to the field. So if you’re interested in web development I suppose this is a good forum to go to if you have a question that can’t be solved with a simple google search.
its cool 
I am new in this forum so i want to know about this forum
I think that this requires further explanation. Exactly what do you need to know that it is not obvious?