1.  Line buttons:  Line buttons may be assigned as outside lines, extensions or one step access to features.  The Basic telephone has 8 line buttons.  The Speakerphone, Displayphone and Executive all have 16 line buttons. 

Next to the line buttons are red/green LEDs which light to show the status of a line or feature.  For example, when a line is in use by someone else, the LED lights red.  When you use the line, the LED lights green.  Another example is when you have new voicemail messages, and the button is programmed as a message (MSG) button, the LED lights red to remind you to check your voice mail.  You access your voice mail by pressing the MSG and the ICM button and entering your security code. 

Other commonly used features programmed on the buttons include do not disturb (DND) which diverts your calls to voice mail and Page for one-way paging through all or some of the telephones.

When the buttons are programmed as extensions, you can call or transfer calls to other telephones in the system by simply pressing the button.  If the other telephone is already busy, the associated LED lights red.

2.  Microphone:  The MIC button controls the built-in microphone which is used for handsfree reply on intercom calls.  It is also used for full handsfree conversation on outside lines.  The Basic telephone does not have a microphone.

3.  Handsfree:  The HF button turns the speakerphone on and off.

4.  Hold and SPD/LNR: The hold button is used to place callers on hold.  The SPD/LNR button is used for speed dial and last number redial.

5.  Volume Controls:  These button control the volume for handset conversation, speakerphone conversation, ringing and display brightness.

6.  Alphanumeric Display:  The Displayphone provides useful calling information such as calling party I.D. and length of call.  When used in a call center application, it displays the number of calls waiting to be answered.

7.  Speed Dial Button:  These buttons are typically used for speed dialing often called telephone numbers.  They may also be used for access to certain features when it is not necessary to have a light associated with the feature.

Other buttons:  C.WAIT (call waiting) can be used to have a second call ring when you are already on the telephone.  The second call can be forwarded to voice mail if you do not answer it.

FLA (flash) can be used to access telephone company features such as three-way calling or transferring callers to cellular telephones (telephone company Centrex line required).

ICM (intercom) is used for dialing other telephone extensions within the system.

TRF (transfer) is used to transfer callers to other telephone extensions within the system.

FEAT (feature) is used to program certain features.