Media servers
Network access to content
Open standards over the network.
There are two main standards for accessing a library of media content: DLNA and HTTP. DLNA allows the library to be browsed with a client such as VLC. HTTP means that you can navigate the content via a web browser, and this tends to offer a fancier user interface, with individual graphics for each piece of content.
Having a separate server enables a setup with a low-power device, such as a Raspberry Pi. That way, the server can be located out of the way and will still work if your main computer is ever out of action or simply switched off.
Most of these servers only use a small part of your total CPU and memory resources if you add them as a piece of software. This might be more power-efficient than running a separate computer, and if you need more resources, adding more memory and a faster processor to your main rig might be more cost-effective than upgrading a server.