Although core memory is obsolete, computer memory is still sometimes called "core" even though it is made of semiconductors, particularly by people who had worked with machines having actual core memory. The files that result from saving the entire contents of memory to disk for inspection, which is nowadays commonly performed automatically when a major error occurs in a computer program, are still called "core dumps". Algorithms which work on more data than the main memory can fit are likewise called out-of-core algorithms. Algorithms which only work inside the main memory are sometimes called in-core algorithms.