Eli5: How does electricity = data?

Question

We have electronics that can do a multitude of incredible things. I understand that data has to do with the binary system, but I can’t get my head around how electricity can be transfered into data… and how that data can then generate images and render graphics, etc. I mean, wut!? Plz hlp, brain cannot compute.

In: 5

Answer 1

Simple example: You have a lightswitch that runs all the way to your friends house. Light on = you’re home from work, come over and hang out, light off = you’re still at work. Congratulations, you have successfully sent information over a wire using electricity.

A computer essentially works the same way, turning an electric switch on and off really fast to send data. The way it does this is by using standard “protocols,” to send and receive data. A simplified example of a protocol might be “The first `on` means ‘start listening,’ and then every 1ms after that record if the wire is `on` or `off` for a total of 8ms.” If both computers know this protocol, they can easily send data back and forth.

This might result in the “packet,” of data being sent such as `01011001` (with `1` being the wire is `on`, `0` being `off`). Computers use binary, so depending on what the receiving computer was listening for, that packet might be interpreted as the number `89`, the letter `Y`, or some kind of arbitrary instruction that the programmers of a certain piece of software decided on (such as your player stepping on a landmine in a video game).

As far as images and graphics, you’re just sending basic data. If you want to send an image, the computer says “hey, start listening for 75,000 numbers I’m about to send you that will represent red, green, and blue values for an image,” and then proceeds to send those numbers. Graphics might send a list of points for the 3D geometry (again, just a list of numbers), or it might just say “you know the shape already because it’s in the program’s code, just draw that shape at X, Y, and Z position,” and sends those numbers.

Of course there are millions of other things that can be sent, but it’s really just up to the programmers to determine how they want to communicate, and what numbers they want to send.