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