How Computer Memory Works? 💻

In different ways our memories make us remember who we are, what happened in the past, learn and retain our skills at a personal level and hope for the future. May be looks like this

Computers or machines act as extensions or clones of humans, as memory plays much the same role. Whether it's a video, audio, some text or some set of instructions for opening something in your computer.

Everything in a computer’s memory takes the form of small units called bits i.e. binary digits which mean there is only possibility of 0 or 1. Each of these are stored in a memory cell or address that can switch between two possible states i.e. 5v or 0v (v stands for volts) for two possible values 0 or 1. Every file or program you either download or write into computer has millions or sometimes trillions of these binary digits decoded back by computer brain (CPU) to form human readable language.

In the recent times the amount of data processed has shown a sharp inclination due to increase in digital life and data driven organizations. This pushes computer scientists into constant struggle for size, cost and speed.

Like how humans process different parts of the brain depending on information, machines also do the same. They have short-term memory for immediate tasks or temporary storage and long-term memory for permanent storage or data persistency. When we run something on our PC it can be an application, program or task our CPU assigns some space or memory in short-area or main memory and performs the following cycle.

This cycle completion is needed for output or GUI display of any program or application. Sometimes we may not even get the results if there is some error in instruction passed and the time taken to process such instructions is called memory latency. Now-a-days to decrease such latency many applications are using multi-level caching which will be discussed in another article. As the computer is getting some instructions and it has to process it faster to do so CPU will access memory randomly from short or main area that’s why name R.A.M (Random Access Memory).

The most commonly used R.A.M is dynamic R.A.M. Where each memory cell consists of a tiny transistors & a capacitor that stores electrical charges in the form of “0” or “1” where 0 means no-charge and 1 means fully charged. Such memories are called dynamic because they just hold charge briefly before they leak away requiring periodic recharging to retain data. However, its low-latency of 100 nano-seconds is also too long waiting for modern machines. So there comes high speed internal memory made out of static R.A.M which consist of six interlocked transistors and doesn’t require refreshing. Unlike DRAM SRAM is expensive in terms of cost and space.

Till now we are working on some short-term memory which is powered, but what happens if there is no power? How do we store our data? To answer such questions, we have secondary memory or permanent memory in our computer where we transfer or save our data which are called R.O.M(read only memory). These have evolved on-time from magnetic storage to solid state drives.

Magnetic Storage

The Magnetic storage, which is the cheapest of all, where data is stored as a magnetic pattern on a spinning disc coated with magnetic film but because the disc must rotate where the data is located in-order to read the latency for such drives is 1,00,000 times slower than that of D.R.A.M.

Optical Storage

On other hand, optical-based storage like DVD and Blu-ray also uses spinning discs but with a reflective coating. Bits are encoded as light & dark spots using a dye that can be read by a laser. Well optical storage is cheap & removable, they have been even slower latencies than magnetic storage & lower capacity as well.

Solid State Storage

Finally, the newest & fastest types of long-term storage are solid state drivers like flash sticks, these have no moving parts instead using a floating gate transistor that store bits by trapping or removing electrical charges with in their specially designed internal structures. They are hard disks of your computer.

So, we’d talked a lot about data storage, working state and how to store but it’s not complete yet as you might have struck up a question just like me.

So how reliable are these millions or trillions of data?

• We often think that computer memory is stable and permanent. However, it degrades very quickly.
• Heat generated from devices and their environment will quickly de magnetize drives and other optical media causing charge leakage in floating gates.
• SSD’s floating gates tend to corrode with repeated writing which makes them useless.
• With data on most recent storage media has less than ten-year life expectancy. So, we tend to back up our data regularly to cloud and even cloud suppliers maintain their duplicates in order to retrieve if one of their drives fails.

Conclusion

On closing note there is immortality whether it can be a machine memory or humans as of now and we hope to achieve something unbelievable and thanks for loading some bits of memory by reading this article. 💖

References

Images: Google Images, unsplash.

Information: Google Search engine , Wikipedia.