http://www.skype.com/
Skype is a software application that allows users to make voice calls over the Internet. Skype-to-Skype calls are free, and you never have to worry about cost, time or distance. Also, calls to landlines and mobile phones can be made for a fee.
Additional features include
Instant Messaging
File Transfer
Video Conferencing
You can use Skype on a computer or get Skype on your mobile phone so you can keep in touch on the move.
Solutions for the office
Share work and talk about it right away. Do it all from your computer. Send any size of file instantly, then start a conversation or a conference in one click to discuss it. Skype makes it easy to work together. Skype improves the way your company communicates — by spending less and doing more. Get online numbers for your office so that clients, suppliers and partners can reach you from landlines and mobiles. Enhance your office communications.
Send
Files
Send files instantly to other people with Skype. No size limits.
Screen
Sharing
Share your computer screen on a free video call so you can show someone exactly what you’re talking about.
Instant Messaging (IM)
Type your conversation in real-time instead of talking. Plus add people to make a group IM where the whole team can talk.
Call Any Number
Call people who don’t have Skype. Dial any phone or mobile number and pay low per minute rates or get a monthly subscription and call unlimited to certain countries.
Talk face-to-face to other Skype contacts free from a meeting room or from your computer. It's free anytime, from anywhere in the world.
Conference Calls
No bridge numbers, no expensive equipment – just add Skype contacts and phone numbers into a group and click Call.
With Skype, businesses work better with free face-to-face Skype video calls between colleagues - home and abroad. Now you can easily share products and designs, in real time, and know when colleagues are available with online status through Skype. Instant decision making with free IM and large file sharing gets work done faster. Businesses can also save money with pay as you go calls or unlimited calling subscriptions for calls abroad.
Working from home
Set up Skype in your home office for the price of a webcam, headset and a broadband connection - no expensive equipment required.
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