In addition to its literal meaning, the term may be applied to a situation when the data written by one circuit can be read only by other circuitry.
Write-only memories also find applications in security and cryptography as a means of preventing data being intercepted as it is being decrypted.
In 1972, WOM, an antithesis of read-only memory (ROM), was introduced as an inside practical joke perpetrated by Signetics.
Such arrangements are common on small embedded microcontroller systems to save costs and can cause difficulties for authors of device driver software.
A large part of this was occupied by the BIOS and the video card, resulting in only 640 kB of contiguous addressable RAM being available.
[9] Locking the frame buffer of a GPU to effectively turn it into a write-only memory can be useful in protecting encrypted data.
The existence of unencrypted material in memory where it can be accessed by the CPU or peripheral devices is a potential security weakness.
This weakness may be alleviated by carrying out the decryption within the GPU and writing the unencrypted data directly to display memory.