Basic Memory/Data storage
RAM is one storage method. RAM (Random Access Memory) is something you can never have enough of (although that can apply to most things). RAM takes information you might not need forever. For example, an sprite for a game is something you want to keep forever, but the fact that at the very moment you are in a certain stage of an animation isn't something to keep. This is the RAM's job. RAM is a quick and easy storage. It's like a pocket for information that can be quickly read as quickly as can be written.
ROM, not to be confused with RAM, is another storage method. A good example of ROM (Read-Only Memory) is a game cartridge. ROM is for things you don't need to modify (or is really important so it SHOULDN'T be modified). For example, your position in a video game is something that is always changing so should go to RAM, but for a game like Mario, the levels shouldn't be changing and aren't meant to change so they go in ROM. For a more technical explanation, RAM is made to be access randomly and changed, where ROM is to be read from. RAM is like a notbook that you take notes and write quick notes, make changes, and refer to later where ROM is like a book you borrow from the library that you read and don't need for much more (and I hope you don't modify that).
Now for the fabled hard drive. The hard drive is different from the others. ROM is nice because you can have, let's say a Wii game, and when you take it out, the information stays the same. That's nice, but you can't write to it, so information can't be saved. RAM is nice, but one it loses power, it's gone (like that long essay you forgot to save in Microsoft Word (#GoogleDocs4ever #CloudTechnology #Ignoremyrants)). So what do we have to compromise? The hard drive. Turn off power? No problem. Information stays. Read AND write information? No problem. Another advantage, hard drives are bigger because of the way they work and what they are used for. A little Mario Kart game disk may have a lot of information for all the carts, maps, characters, physics, etc., but compared to the Instagram database with 60,000,000 pictures uploaded daily (click here for reference), and about each photo at anywhere from 100-200 KB (kilobytes) (reference), Instagram hard drives would have to withstand writing about 72 billions bits (refer to vocab at end of post to understand bits) of data devery day. So if you think about it, that's a lot of data being stored on computers. So hard drives have to work. Imagine if all those pictures were stored on RAM. If there was a power outage, thousands of users would lose all their like, comments, and most importantly, pictures.
Next time you upload a picture or post to social media, just think about and thank the hard drive behind storing your post!
In the next post, I'll discuss how a hard drive does its magic!