In its current state, this document is not a description of a marker but of the use of a marker in some AT&T; (aka Bell Sysem) equipment. As such, it is limited and not representaive of the concept. Telephony is a world wide concept and is not restricted to the technology developed by AT&T.;

Computers are not limited to stored program devices. The example of Collosus which was used to break the Enigma codes is a good one. it is widely regarded as an early computer and was not a stored program computer. The comparison of the marker to a computr emphasizes its funtion and role.