How Smoke Alarms Work. Smoke alarms, which are also called smoke detectors, work by constantly checking the air for traces of the gasses and smoke particles produced by a fire. There are two types of smoke alarms-ionization alarms and photoelectric alarms.moke alarms, which are also called smoke detectors, work by constantly checking the air for traces of the gasses and smoke particles produced by a fire.
Exporting items from OST to PST is the best way to create backup of OST file. If you are connected with Exchange server, you can easily do this via manual method. In other case, you should try some third party tool.
However, it is not designed for full system backups. 1  Answer ID 12962: How to install the WD Backup application. 2  Answer ID 12963: How to backup up files using the WD Backup application. 3  Answer ID 12937: How to restore a backup made with WD Backup on a PC.  Answer ID 11900: Files that are not included in a WD Backup job.