Skype is a program used for IP telephony. Using this you can call any other computer that is connected to the internet and has skype installed. You must create a user account to be able to use Skype.
Computers set up by the IT-Department
Please use Windows Software Centre to install Skype.
Computers NOT set up by the IT-department
If you have a computer that is not set up by the IT department, you can still use Skype. Then you will have to download and install the program yourself. You can download skype here