‘The Internet’ is used to describe a network of connections between computers. Using Reddit as an example, Reddit has several computers that run the programs that make Reddit and store all the information. We call computers that specialize in this sort of thing a server. While you might have just one computer/phone, most companies don’t use just one server, and you can think of it like a chain of stores. Let’s say you want to get something from Starbucks. Chances are, there are many ways for you to get to your closest Starbucks, and if that one is busy or closed there are others around you can use instead. Back to the Reddit example, Reddit has many servers and Reddit handles which server you connect with and you don’t have to worry about all that, but just know that it’s a thing that happens.
On an individual computer/server basis, it is possible to run out of storage. The reason this doesn’t happen is that companies are pretty much constantly expanding their server capacities and building more servers to store all the information, and they usually do this by building a new building and filling it with computers. There are a lot of these buildings where I live.
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