Hi Glenn,
Phone button templates let you assign speed dials and call-handling features to programmable buttons. Call-handling features that can be assigned to buttons include Answer, Mobility, and All Calls.
Ideally, you modify templates before registering phones on the network. In this way, you can access customized phone button template options from Cisco Unified Communications Manager during registration.
*The default Cisco Unified IP Phone 9971 template that ships with the phone uses buttons 1 and 2 for lines.
* Additionally, some of the call features in 9971 are implemented using additional buttons and feature keys. There are dedicated keys for call feature 'transfer', 'conference' and 'Hold.
*Other call features like 'Call Park' , 'call pick up' etc are configured using Feature Buttons (Buttons on the left hand side of the screen) and you have to use phone button template instead of soft key template to configure the same.
The lines on the Cisco 9971 on the right hand side are the not configurable for lines .
This buttons are called “Session buttons”. Session buttons (right side)—Use to perform tasks such as answering a call, resuming a held call, or (when not being used for an active call) initiating phone functions such as displaying missed calls. Each call on your phone is associated with a session button.
Each corresponds with an active call or a call function. Pressing the button takes the default action:
Active calls—Pressing the button takes the default action for an active call. For example, pressing the session button for a ringing call answers the call and pressing the button on a held call resumes the call. Session information, such as caller ID and call duration, appears on the phone screen next to the session button.
Call functions—When a session button is not being used for an active call, it can be used to initiate functions on the phone, as indicated by the adjacent phone screen icons. For example, pressing the session button can display missed calls, take the phone off hook, or dial your voice-messaging system (with a Voicemail icon).
In addition refer this link
http://www.cisco.com/en/US/docs/voice_ip_comm/cuipph/9971_9951_8961/8_5/english/user_guide/book_911/yourphone_rt.html#wp1022201
Hope this helps.
