Memory dumps are usually stored on the local file system, which may make them easily accessible. Erasing Erasing data from memory may be more difficult than one might think. Deleting usually only means removing a system file entry that points to a file. The file still exists somewhere, until it gets overwritten. Even when overwritten, files can still be recovered, given the right equipment, software and knowledge.
Some software utilizes overwriting schemes to try to remove files from magnetic memory.
The software does this by overwriting files multiple times, alternating overwriting with binary ones, zeroes, patterns of ones and zeroes, and random data. The concept behind this kind of overwriting scheme is to flip each magnetic domain on a disk back and forth as much as possible, without writing the same pattern twice in a row. Basically each track of memory contains an image of everything ever written to it, but each layer gets smaller and harder to retrieve the further back it was made. No one really knows how many passes are sufficient. To avoid the risk, try not to write to the disk at all.