HDD Temperature is a nice little program to know the temperature of your hard disk, and whether it is normal or not.
SMART (Self-Monitoring, Analysis, and Reporting Technology, or S.M.A.R.T.) is like a monitoring system (built into hardware) for computer hard disks to detect and report various parameters on reliability. By analyzing this data, we can predict future failures. So, it is a really good feature, in the sense, we could backup all our important data before a hard disk fails.
HDD Temperature supports the hard disks using this feature. So, the data it provides is reliable. But this program doesn't do much. It only reports the temperature of the hard disk, and whether it is high or not.
It has settings which could be set to automatically shut down or put the computer into sleep in case there is an overheating. It could be set in 2 levels of temperature, "Urgent" and "Critical" temperatures. "Urgent" is a low temperature, and the "Critical", some high temperature, which can damage the hard disk.
Anyway, it’s a small program, which does pretty good on monitoring disk temperature.