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You can use Skype to text chat for free with any other Skype user. In order to do so, they must be on your contact list. Select their name from your contact list and start typing your message in the chat box. If the user is not online, your message will be delivered the next time they log in. You can voice chat with any Skype user for free. Select them from the contact list and then press the green Call button. A notification will appear on their screen letting them know that you are trying to reach them. You can only initiate voice calls with users that are online. You can video chat with any Skype user for free. Select them from the contact list and then press the green "Video call" button. A notification will appear on their screen letting them know that you are trying to reach them. You can only initiate video calls with users that are online. You can purchase a Skype phone number for $5 per month. This will allow anyone to call you from any phone. This is especially useful if you are traveling in another country or are moving to a new area. You can choose the area and country code when you set up your Skype number. The Skype number acts just like any telephone number. The caller will receive charges based on standard rates. For example, if the caller lives in New York, and your Skype number is in London, the caller will be charged standard international rates. You can use Skype to call any phone number, but you will need to purchase Skype credits in order to do so. Click the Phone icon above your contact list to open the phone dialer. Skype credits can be purchased either through the application, from the Skype website, or by purchasing Skype cards from retail outlets. Different calls will have different rates.

Summary:
Start a text chat. Start a voice chat. Start a video chat. Set up a Skype number. Call a mobile or landline with Skype.