THE STUFF THAT MAKES YOUR STUFF WORK: Non-volatile memory

Believe it or not, the most common form of storage in the world didn’t exist at all in 1970. At this point it’s hard to find anything that doesn’t have non-volatile memory.

There was a time when electrical devices were simple. Their actions were dictated by switches and gears. Even electronic devices followed predictable patterns that never ever changed. The world of electronics was upended by the invention of general-purpose processors like the Intel 4004 (a distant cousin of which probably powers your PC today.) The general purpose process could interpret any instructions you threw at it, but there was a hitch: you had to be able to store those instructions. That\’s why you need non-volatile random access memory, commonly called NVRAM.

The difference beween NVRAM and ROM, the other sort of solid-state storage, is that ROM is forever. I mean, you lay stuff down on a chip and you’re done, doesn’t matter if you want to change it because you can’t. NVRAM is, at some level, changeable. Early NVRAM chips could only be erased completely, meaning one change and you wiped the whole thing. By the 1980s, “flash” memory was developed which stored information permanently but could be erased literally bit by bit.

NVRAM also differs from regular random access memory. RAM memory is super-fast compared to other forms of storage but it requires constant power. NVRAM stores things permanently whether or not there is power.

NVRAM is used for everything from remote controls to supercomputers to store information that must survive a loss of power, such as the codes in your universal remote or the codes required to launch a nuclear attack. It\’s so stable that NVRAM chips have been known to survive explosions and drops from planes.

There are a number of technologies used to produce NVRAM, but they all have the same result, meaning a circuit that changes somehow when electricity is applied, and keeps that change when there is no electricity. Some forms of NVRAM are designed to be super-stable and can be used for military and space purposes, while others are designed to be super-cheap for consumer use. Stack together enough NVRAM and put an industry-standard connector on it, and you have a “solid state drive,” a device that acts like a traditional hard drive but is much, much faster and quieter.

NVRAM is used for storage on everything from washing machines to thermostats to smart watches. It’s literally everywhere, and the world we live in wouldn’t work without it.