A Disk on Module (DOM) is a type of computer memory that is connected directly to a motherboard through a data connection and acts as a hard drive. This is nonvolatile memory that does not require power to maintain data, and is effectively similar to flash memory used in other devices. A Disk on Module is typically found in applications in which a Hard Disk Drive (HDD) would be unsuitable due to the environment in which the computer is used. It functions in much the same way as a Solid State Drive (SSD), and damage to the DOM can render data irretrievable.
The appearance of a Disk on Module is similar to a stick of Random Access Memory (RAM), though it is typically a bit thicker in size. A DOM is usually designed with pins that allow it to attach directly into a data connection for hard drives on a motherboard. It can use the same type of connection as a standard HDD, but does not require a ribbon cable to do so, instead it plugs directly into the board. This allows a Disk on Module to require much less space in a computer than a standard HDD or larger SSD.
In most ways, however, a Disk on Module can be used as a hard drive, just like other types of storage on a computer. It is nonvolatile memory, which means that it does not require power for data on it to be saved. This is in contrast to volatile memory like RAM that loses stored information once power is turned off.
One of the major benefits of a Disk on Module is that it does not have moving parts or a physical disk that is read for data. Hard drives that use a disk, such as an HDD, have an optical reader that scans the disk as it physically spins to retrieve data. If the disk becomes damaged or the reader is unable to function properly, then the drive can become corrupted. This often occurs if someone drops an HDD, while dropping a DOM does not necessarily damage internal components or the data on it.
One of the major drawbacks of using a Disk on Module for storage, however, is the way in which data is retrieved. If part of an HDD with a physical disk is corrupted, then other parts can still be read using special equipment and software to recover data on it. A DOM, however, cannot be accessed in this way. If part of a Disk on Module is corrupted, then the entire drive can be inaccessible and all data on it is lost.