Karma has a simple business model: we sell mobile data at a small profit. Instead of making mobile data into an amorphous "service" with corresponding "subscriptions" and "contracts," we simply sell data as a product to be consumed by our customers at their own pace. But what does that even mean? How can data be a "product," and how can it be "used"? What is a GB?
A GB (or "Gigabyte") is roughly one billion bytes. To be precise, Karma and other mobile providers measure data by the "GiB," which is actually 1,073,741,824 bytes, but it's called a GB anyway thanks to the not-always-straightforward history of computer science and marketing. If this distinction worries or confuses you (it bugs the hell out of me!), I suggest this doozy of a Wikipedia article.
So, what is a byte? It's a unit of computer memory, typically large enough to hold a single character (like the letter "A" or the digit "4"). As you might guess, one billion bytes stores a lot of characters — roughly one thousand books worth of information. If all you ever used the internet for was to send emails and download books, 1GB could last you a long time. But, for better or worse, the internet has cat pictures.
The CD-ROM Bill Gates is holding stores more information than the paper below him
As soon as you're storing something more complicated than a text file, the number of bytes required balloons rapidly. A single pixel in a photo, for instance, can require three or more bytes to represent its color information (one byte each for Red, Green, and Blue). Multiply those pixel by millions per photo (an iPhone, for instance, takes 8 megapixel photos), and you've got a lot of bytes. Video exacerbates the data requirements, displaying 24 or 30 images per second. There are a number of compression techniques that are used to keep sizes down, but there's only so much you can compress a photo, video, or audio file before it looks or sounds terrible.
The internet is a method for getting these bytes from point A (usually a server) to point B (your phone or computer, known as a “client”). Internet protocols like TCP/IP and HTTP add a bit of overhead to communicate to a server what exactly it is you’re requesting. TCP/IP will even re-download parts of a file to make sure you end up with an intact digital copy, no matter your connection quality.
When browsing the internet, the typical webpage — a conglomerate of images, text, and behind-the-scenes scripts — is 1.6MB (1.6 million bytes). That's data your browser requests whenever you type in a URL or click on a link. Each little component of a webpage is found through a rapid series of HTTP requests to wherever those files live on remote servers somewhere. If your browser has seen a recent version of that file before, it might have it “cached” on your local device, which means you won’t have to download it again.
Of course, there's a lot more data usage than just happens in the web browser. Your phone apps might update, your photo library might sync, your email client might download some messages with big attachments. You can sort of think of each of your devices as "thirsty" for WiFi, and they can slurp a lot of data as soon as they get a connection.
This isn't usually an issue with your typical home or work WiFi — there's a reason Time Warner and Comcast like charging $100 a month for internet — but it's something to watch out for when you pay by the Gigabyte (in the case of Karma) or have a strict data cap (in the case of most mobile providers). Dave Ford, part of our support team, has put together a post about how to manage background updates to save data, and another post detailing exactly how much data different applications use.
A good rule of thumb is text < photos < GIFs < videos, in terms of experience-per-byte. With 1GB of data you could send a few thousand emails and upload hundreds of photos, or you could watch half an episode of House of Cards and a few Corgi GIFs. Same Gigabyte, different priorities.
This GIF is 834KB of adorbs
But what's most important to remember is that it's not being connected to the internet that uses data, it's what your devices request for transfer. Just like sitting in your car doesn't use gas, it's when you push on the accelerator. Once you get in the habit of turning off background updates, and saving media-heavy experiences for later, you can get a lot more mileage out of the mobile data you buy.