what is skype?Is that use to make call free

hi
i am normally chat using google talk or yahoo messenger .but i want to know about skype .i heard that it provide free call any where is that true
is any body using it currently ??how its performance is ??please any one can help me ?
thank you.

hi ,
using skype you can do free Skype-to-Skype calls ,you can make calls to phones and cell phones anywhere in the world at great rates.you can also make free video calls.voice quality is good .
you need to download and install it first .it can work with :
Windows
Windows (Business version)
Windows (Beta)
Mac OS X
Linux
Windows Mobile
WiFi phones
Cordless phones
3 Skypephone
Nokia N800/N810

it has Call phones and mobiles at great low rates per minute.




Features

* Free PC to PC calls to people anywhere in the world.
* Free video calls – plus get more detail than ever before with High Quality Video.
* Call phones and mobiles at great low rates per minute.
* Instant message for free when it’s not a good time to talk.
* Forward your calls to your mobile when you're offline.
* Send SMS messages to people on mobiles.
* Comes with the Google Toolbar (optional install).
go here and download it.

http://www.skype.com/download/skype/windows/

hi
go through the site but i am confuse in what is free and for what call rate ??
is there any need to register to use this service ?

hi
to use Skype you need to install it no need to register .
First international call is free. but then you have to pay for per sec.
call rates are different .you can use it from several device but you need to
install their respective Skype application. call rates are fare so affordable .