From desktops to laptops, to cell phones and even to modern video gaming consoles (2021 — PlayStation 5/Microsoft Xbox Series X/Microsoft Xbox Series S), there is a multitude of computers available to people. We use computers for so many reasons, including but not limited to: internet access, playing video games, researching news, watching/listening to entertainment, and so so much more.
The basic idea is that for most computers above, each machine will be used for one person/purpose. For instance, a Dell Gaming PC may be used for playing the latest Batman game at 4k resolution and at 60 frames per second.
The same cannot be used at the same moment to play Crisis 3 at 4k and 60 frames per second reliably — at least, not any machine I have ever seen as of 2021. The basic idea of all of the computing devices above is centered around personal computing — they are designed to give an outstanding one-on-one experience.
What about data that needs to be continually available to 10 … 100 … 1,000 people? You need that same computing power, but the experience needs to be group-focused and not personal.
To solve this problem, the concept of a server was created. A server, simply stated, is a computer that is configured to serve EVERYONE WITHIN A GROUP AT ONE TIME, doing simple or quantum complex tasks individually at the same time.
Originally, you saw higher-specification (i.e., computer comprised of parts that could handle larger personal workloads — such as playing the Crisis game at 4k, 60 frames per second in 2021) personal computers being used as servers.
To do so, you needed to maximize the amount of available computing (CPU chip), storage (hard drive size and speed), and network (fastest-available network card and network connecting to all the potential users in the group it would serve).
In 2021, the server is more a special type of computer that has parts that are built with the mindset they will be used by multiple people at the same time, combing some of the most powerful hardware available in a smaller case.
Furthermore, there are now software versions specifically built for server functionality. Instead of Windows 10, on a modern server, you would load Windows Server 2019 or Red Hat Linux Enterprise version 7. You typically have multiple network connections that can be either bridged (wired to the same network connection for much more data flow) or used separately in parallel (each port connected to a different network connection which allows more connected/alive time if one network connection goes bad). This and more allows the modern server to deliver more accessible services with consistency.
In addition, the cloud is ‘virtualization in another owner’s datacenter.’ If I can name one device type that is dominant in a datacenter, it is the server.
To conclude this, servers are computers configured to serve multiple people with multiple tasks at one time and at various levels of complexity and execution time.