Attribute
S.M.A.R.T. attribute is a specific property of disk being monitored. Every S.M.A.R.T. attribute has a set of properties: attribute value, its threshold, worst attribute value and raw value. Specific threshold is assigned to each attribute. Once the attribute value drops below this threshold, S.M.A.R.T considers disk to be faulty. Some attributes are considered life-critical and others are merely "informative". T.E.C. with an "informative" attribute does not necessarily means drive failure.

Attribute value
Attribute values are used to represent the relative reliability of individual performance or calibration attributes. The current attribute value is the normalized raw attribute data. The value varies between 1 and 100. The closer the value gets to 1, the higher the possibility of a failure. The device compares the attribute values with thresholds. When the attribute values are larger than the thresholds, the device is operating normally.

Raw attribute value
This is a raw attribute data. Usually it shows exact amount of time, attempts or errors. For example: the raw value of attribute Temperature is a drive temperature in Celsius degrees, the raw value of Power on hours count attribute is a amount of hours when drive was in power-on state. You can view the Raw attribute value in the Text Report (Open SMART Info tab and press Report button)

Attribute threshold
This is the lowest limit of a varying attribute value. S.M.A.R.T. compares the attribute values with the thresholds to identify a failure. Each attribute value has a corresponding attribute threshold limit. The numerical value of the attribute thresholds are determined by the device manufacturer through design and reliability testing and analysis. Attribute thresholds are set at the device manufacturer’s factory and cannot be changed in the field. The valid range for attribute thresholds is from 1 through 253 decimal.

Worst value

This is the worst attribute value among the attribute values collected to date. This value indicates the state nearest to a failure so far.

What is T.E.C?
T.E.C. stands for "Threshold Exceeded Condition" and basically means a failure. If one or more attribute values are less than or equal to their corresponding attribute thresholds, then the device reliability status indicates an impending degrading or fault condition.