itssami

many of u guys would already have noticed that now a days , on most of the websites , when some one sign in...as he puts his desired username in the textbox , the page shows that it is not available or it is available...without pushing any button etc.. and the second thing , when some one writes the password , on the same screen , it shows that password is weak or password is strong... i think it is done with php ... can some one give me a link to any page where i can access these scripts ? or some one can help me regarding this ?? Thanks for helping always.

Im looking for a php script/tutorial which imports the email adresses from adress books and send them mail ?? for example in many community websites , there is an option that , if some one gives his/her email and password..then they import the email adresses from that persons adress book or tell that it was wrong password etc.. i found couple of scripts by searching google but they are not free..i still wish to get some thing free.