One of the major purposes of an alarm is to alert the operator of any abnormal condition being monitored. The operator should then acknowledge the alarm, indicating that he/she has been seen it. This is separate from the issue of taking corrective action, if any, which might not happen right away. It is also separate from the issue of whether the alarm condition returns to normal, which it might do on its own, even without any external intervention. For example when an high temperature is reached, if the cooling fan start, it will cool down the system and hence the alarm condition will no longer exists. Acknowledgment merely indicates that someone has noticed the occurrence of the alarm. A high or medium priority alarm usually requires acknowledgment, while a very low priority alarm might not. Although the condition that generated the alarm may go away the alarm itself is not considered handled until it is acknowledged. This is very important and it could be useful to improve and optimize the system.