A server pc is essential has specifically designed hardware designed to run 24 hours a day, 465 days a year. Server pcs are capable of handling heavy loads and dash out a good sum of computation.
These usually called Xeon servers as they use Intel Xeon processors at their centers. These processors can handle heavy details of ram, which can be all the way up to 512 GB. Most major companies have server pcs which handle all of the data storage, sorting and accessibility throughout their offices.
If you want to use a Xeon server as a massive storage solution, you can fit it with hundreds of terabytes of storage space. Companies like YouTube, Facebook, twitter etc. have these massive storage servers with billions of terabytes of storage available.
These servers can also be used for database management in offices, hospitals, schools, laboratories, data centers, website hosts and more.
Essentially, at the heart of any network there is a sever which is controlling the flow and handling data, providing meaningful way of communication between different users as well as being a link factor which connects a user to many websites around the web.