Databases

Also, inside servers, we have databases, which are sets of structured data for your website.

While a simple image or code sheet is stored in a folder just like on your computer, the information that a particular picture of a beautiful dog is a user’s profile picture is registered in a database. 

So, for your website to load its users’ profile pages, it has to access not only your folder but also your database.

So it “knows” that the user is visiting the profile page of your auntie and that she has a profile picture of an apple pie. This prevents loading images at random.