Skype is free software that can be used to video conference between 2 computers or between a computer and a mobile device (iPhone, iPad etc.)
Things you need before you video conference with Skype:
Getting Started with Skype
Add Contacts
Before you can video call someone you will need to find out their "Skype Name" and add it to your Skype contacts list. When you add a contact you will also be asked to send an email to that person requesting permission to video conference with them.
Making a Video Call
You can video call anyone anywhere in the world for free as long as they are in your Skype contact list and you have all of the items listed above. *Please be aware that no matter how much planning and testing you do before your video call you cannot always control what happens to the call on the other end (sound & video quality, internet speed, microphones etc.)
Troubleshooting:
The person can't hear my voice or I can't hear their voice.
Check the microphone settings and make sure the speakers are turned on and plugged in. In Skype click on Tools/Options/Audio Settings (Windows) or Skype/Preferences/Audio-Video (Mac). Here you can test the microphone and test the sound. Make sure that Skype is using the correct microphone and the correct speakers are listed. Check your computer's microphone and speaker settings (Windowx 7), (Mac OSX)
I can't get my webcam to work.
Make sure your webcam is installed properly. You can test your webcam within Skype. Click on Tools/Options/Calls/Video Settings (Windows) or Skype/Preferences/Audio-Video (Mac). When your webcam is installed correctly you will see a preview of yourself.