Ring Central is the telephone call center application integrated with Salesforce. If you are assigned a Ring Central phone number, you will be able to make phone calls from your computer directly from the Ring Central application or from Salesforce.
When a user is logged into Ring Central, phone numbers in Salesforce turn Blue, indicating that you are able to use the Salesforce "Click to Call" functionality. You can just click on the blue phone number and Ring Central will open and start dialing that number.
When a call is complete, you will have the ability to add notes and associate the call with a Case for tracking interactions.