Call park and retrieve are very useful if you need to continue your call, but you can't transfer the call to your phone because the call will go to voicemail before you can get back to your desk to answer it. Or, a receptionist or coworker can use call park, so you can get to your desk to answer it.
The transfer feature allows you to send calls to individuals within or outside your office. If you want to speak with the person you are transferring to first, use the consultative transfer option. If you prefer not to announce the call before transferring, use the blind transfer option.
Busy lamp fields is a feature that can be programmed on your phone to see the phone status (idle, ringing, on a call) of other extensions. Learn how to use busy lamp fields to monitor, answer, transfer, and conference calls.