What Is a Server?
Servers are high-powered computers built to store, process, and manage network data, devices, and systems. Servers are the engines powering organizations by providing network devices and systems with adequate resources. For businesses, servers offer critical scalability, efficiency, and business continuity capabilities.
Whether it’s hosting a data-heavy website, setting up a shared drive for a department, or managing thousands of queries every minute, servers are the vehicles for hosting and processing-intensive workloads that go beyond the capabilities of a traditional computer.
What Does a Server Do?
Servers can do everything a standard desktop computer can do and more. Vice-versa, computers can run server processes, but do so far less productively. Generally, servers offer the following features to the networks they serve:
- Scalability to serve a growing or fluctuating number of devices, users, and workloads
- High processing power with rising CPU and RAM specs to handle network workloads
- Reliability to ensure critical systems remain online and available
- Collaboration between personnel with access to shared network resources
- Cost savings over time because servers can reduce stress on network devices
The Client-Server Model
Servers that power other devices on the network are referred to as host servers. The in-network devices receiving resources from the host server are known as clients. The following graphic offers a quick look at how servers and clients work within a network.
Server Form Factors
Servers come in all shapes, sizes, and designs. However, the structure or form factor of servers typically falls into three types.
Rack Servers
A rack server is a general-purpose, mountable, and rectangular machine that stacks neatly into metal rack frames, thus optimizing space usage.
Read more: Top Rack Servers of 2021
Blade Servers
A blade server houses multiple modular circuit boards called blades that don’t need CPUs, network controllers, and memory while also fitting in a rack frame.
Read more: Best Blade Servers for 2021
Tower Servers
A tower server is a lightweight, stand-alone chassis often used by small businesses for its strong configuration and customization features.
Read more: What Is a Tower Server?
For a full breakdown of how servers differ by structure, read our guide to Blade Servers vs Rack Servers vs Tower Servers.
Server Software
Server Operating Systems
Server operating systems (OS) are the core programs that enable all server functionality. Operating systems for servers must be able to handle:
- Providing command-level interface (CLI) and/or a GUI display
- Comprehensive management of users, security, and processes
- Advanced hardware, software, and network configuration
- Managing and monitoring client computers, software, and activity
- Installing and deploying applications and patches to clients
Types of Server OS
- Linux OS
- Unix OS
- Windows OS
- Ubuntu OS
- Open Enterprise Server OS
- Red Hat Enterprise Linux OS
- Mac OS
Learn more about the most popular operating system for servers in our Best Linux Server Distros for 2021.
What Are the Different Types of Servers?
Other Types of Servers
Domain Controller
Foundational to networks, domain controllers store the Active Directory and AD tools to manage users, permissions, devices, and group policies.
DNS Server
Adjacent to the domain controller, Domain Name Service (DNS) servers resolve the conversion of names into IP addresses for network systems.
DHCP Server
A Dynamic Host Configuration Protocol (DHCP) server automatically assigns network devices with the router, gateway address, DNS address, and IP address data.
Patch Server
The more extensive your network, the more likely you are to need an update server (or patch server) devoted to deploying updates. Patches resolve bugs and vulnerabilities and deliver new features for apps.
Phone Server
Connecting with a Private Branch Exchange (PDX), a phone server (or VoIP server) enables phone switching devices for managing internet-phone networks.
Email Server
Less common because of cloud solutions, email servers host email data. Examples of email servers would include SMTP relay or Microsoft Exchange Server.
Monitoring Server
A monitoring server handles the job of scanning the network and monitoring equipment health, as well as specs like CPU, RAM, and hardware space.
CCTV Server
Closed-circuit television (CCTV) servers, or building security servers, store audio, video, and sensor data related to the physical security of organization premises.
Terminal Server
A terminal server, or remote desktop server, enables remote users to access network resources for business continuity.
Load Balancing Server
For websites, applications, and software with varying and intensive workloads, load balancing servers can reallocate demands between other servers.