If you've ended up here, you're probably wondering what Raspberry Pi can be used for. In many places, you can read about the versatility of Raspberry Pi and the many possibilities it offers, but what does that actually mean?
Some Theory about Raspberry Pi
The mentioned posts about the versatility of Raspberry Pi don't come out of nowhere; it's all thanks to the support for advanced operating systems. The basic operating system is Raspberry Pi OS, a distribution of Linux based on Debian.
Yes, it's a full-fledged Linux, which is often used in professional applications. Many internet services are installed on Linux servers, including this blog. Thanks to this, we have a wide range of available software that we can configure on our Pi.
It's also a very economical solution; aside from the relatively low cost of the device, the power consumption, in the case of my server, did not exceed 7 kWh per month.
When choosing Raspberry Pi for yourself, you should consider your requirements and match them to the appropriate Pi version. For simple applications, the Raspberry Pi Zero 2 is sufficient, while the greatest capabilities are available with the Raspberry Pi 4 and 5. To start your journey with Raspberry Pi, I recommend choosing boards that support 64-bit systems, such as the Raspberry Pi 4, 5, and Zero 2. This doesn't mean that older boards are useless; on the contrary, they are still excellent hardware on which a significant amount of software continues to run. Unfortunately, the slightly older architecture and lower computing power may not be sufficient from today's standards' perspective and may require additional effort in configuration.
ARM Architecture
An important aspect to be aware of is the architecture of the processors used on Raspberry Pi boards. All Pi boards are based on ARM processors, an architecture that is gaining increasing popularity but is decidedly less popular than x86 processors. As a result, it may turn out that the software you want to install on your mini-server is not compiled for ARM, so you will have to compile it yourself if the source code is available. Unfortunately, this fact can be a challenge for beginners and may also cause problems for more experienced users due to the lack of adaptation to ARM's specifics. In a worse scenario, when the source code is not available, you may need to try to configure emulation of an x86 environment, which is a more complicated process and is associated with a decrease in program performance. This approach may also result in failure when running our service. Fortunately, Raspberry Pi and ARM architecture have been in the market for a while now, so a large part of the software has already been adapted to work on ARM.
Network Infrastructure Requirements
All the things described in this post are based on networking. When it comes to a local network, all the examples will certainly work. Unfortunately, things get more complicated when you want to have access to your resources from anywhere on Earth. The basic issue is a public IP address. You need to determine whether your internet service provider assigns you an individual IP address visible on the internet and whether they allow external communication. The easiest way to find this information is on the provider's website or by contacting them directly. Another aspect to watch out for is a dynamic IP address. This is a situation where, despite having an external IP address, it changes cyclically. Fortunately, there are Dynamic DNS services that monitor our IP address continuously and update this information in the domain we received from the DDNS service in case of any changes. For your own server, it's also a good idea to get your own domain so you don't have to memorize an unattractive IP address. And I'll suggest right away that you can link your own domains to DDNS services, so you don't have to use the domain provided by the service provider.
Practice, or Actual Use of Raspberry Pi
NextCloud
NextCloud is free software for file transfer and storage. It's a private alternative to solutions like Dropbox or Google Drive. NextCloud is compatible with Raspberry Pi, and for this purpose, I highly recommend using Pi 4 or 5. You can upload your files using a browser interface, mobile app, and client for Windows, macOS, and Linux systems. One of the big advantages of NextCloud is the addition of support for U2F keys. It's worth looking into this software to ensure space for your and your family's data without paying additional subscriptions.
WireGuard
WireGuard is a free VPN server. It's a useful tool that allows you to securely connect to your local network, for example, to access a device that cannot be accessed from the internet. Another use of VPN is to change your location as seen by other servers. This can be useful when traveling abroad, where some services may not be available outside the country you live in. For example, being in the United States, with a VPN located in Poland, internet services will see that our connection is coming from Poland.
Web Server
Having your own server is the perfect place for your own website. If you want to have your presence on the web, share your passion, have your own business card, or have any other idea, you can realize it with Raspberry Pi. There are many solutions available, with integration of PHP, Python, or Java posing no problem. When you need a database, you can install it too.
Samba
Samba is another free server, this time used to create network drives. Unlike NextCloud, which requires synchronization, Samba creates a share on the local network that you can connect to as a drive on your computer without any additional software. This can be especially useful when you need to transfer a large amount of data, and you don't want or need those data to be available over the internet.
Minecraft
If you like playing Minecraft, this message might make you happy. It's possible to run a Minecraft server on Raspberry Pi. While the Raspberry Pi might be too weak for hundreds of players, it works perfectly as a small server for friends. This is one of the more demanding tasks for the Pi, so the best choice would be the latest Raspberry Pi 5.
GitLab
This suggestion is mainly aimed at programmers, and it's not a joke. You can really run a GitLab instance on such a small board as Raspberry Pi. For the uninitiated, GitLab is software whose main purpose is to store source code of projects. It's a very useful tool that gives you a lot of control over your projects. With GitLab, you can also run container registries where you can store your Docker images.
Other Suggestions
Raspberry Pi offers a lot of software waiting to be installed. The examples mentioned above are just a small sample of what you can configure. There are many services, SmartHome control centers, tools for programmers, servers for networked printers and scanners. If you need a solution for everyday life, there's a good chance that such a tool is already available. Detailed configurations of individual services will be coming to the blog soon, so stay tuned!
Is Raspberry Pi Absolutely Necessary?
Of course not. I describe the above examples based on Raspberry Pi because it's a wonderful device for learning networking, programming, and electronics. The services described in the article should work without any problems on other single-board computers, servers, or terminals running Linux. Of course, you need to take into account the computing power of specific devices. I successfully ran and used the described services on Raspberry Pi, which is why I recommend this platform.