Physical properties of hardware devices, such as remanence of magnetic media, residual charge of ROMs/RAMs, or screen burn-in may still retain sensitive data after a data removal process has taken place and power is removed. Recovering data after erasure or overwriting is possible due to a phenomenon called data remanence. For example, if the same value is written repeatedly to a memory location, the corresponding memory cells can become physically altered to a degree such that even after the original data is erased that data can still be recovered through physical characterization of the memory cells.