Editing On- and off-hook (section)

==On-hook==
[[File:Original Trimphone, On Hook.JPG|thumb| On hook telephone handset]]
The term '''on-hook''' has the following meanings:  
* The condition that exists when a telephone or other user instrument is not in use, i.e., when idle waiting for a call. Note: on-hook originally referred to the storage of an idle telephone receiver, i.e., separate earpiece, on a switchhook. The weight of the receiver depresses the spring-loaded switchhook thereby disconnecting the idle instrument (except its bell) from the telephone line.
* One of two possible signaling states, such as [[SF tone|tone]] or no tone, or [[Ground (electricity)|ground]] connection versus battery connection. Note: if on-hook pertains to one state, off-hook pertains to the other.
* The idle state, i.e., an open loop of a [[subscriber line]] or [[Private branch exchange|PBX]] user loop. 
* An operating state of a [[telecommunication circuit]] in which transmission is disabled and a high [[Electrical impedance|impedance]], or "open [[Electronic circuit|circuit]]", is presented to the link by the [[end instrument]](s). Note: during the on-hook condition, the link is responsive to [[Ringing (telephony)|ringing signals]].

The act of ''going on-hook'' is also referred to as ''releasing the line'' or ''channel'', and may initiate the process of [[clearing (telecommunications)|clearing]].