What Is a Server? | Definition, Types, and Features

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A server is a specialized computer or software system designed to provide services, data, or resources to other computers, known as clients, over a network. These services can range from delivering web pages and email to storing and managing files or running applications. These machines run on a client-server model, where clients request specific services or resources, and the server fulfills these requests.

Servers are distinct from personal computers in their purpose and capabilities. While personal computers are optimized for individual use and have a user-friendly interface, servers are built for performance, reliability, and scalability to handle multiple requests from numerous clients simultaneously.

The role of a server is akin to that of a librarian in a vast digital library. It organizes and stores information, ensuring it is accessible, reliable, and secure for anyone who seeks it. The sections below aim to answer the question “What is a server?”

This guide will explore the various types of servers, and their functions, components, and significance in the digital age. We will also talk about the best practices in setting up and managing servers, as well as some real-world examples.

What does a server do?

Servers are the digital workhorses that power much of our modern world. To understand their significance, it’s essential to grasp the wide array of tasks they can perform. Here, we explore the multifaceted role of servers and the core functions they execute:

• Data storage and retrieval: One of the primary functions of a server is to store and manage data. This data can encompass everything from files and documents to databases and media content. Servers provide a centralized location for storing and retrieving this information, making it accessible to authorized users from various locations.
• Website hosting: When you browse the internet, the web pages you access are typically hosted on web servers. These servers store the website’s files and deliver them to your web browser when you request a page. They handle everything from text and images to videos and interactive features.
• Email services: Email servers manage the flow of electronic messages. They receive, store, and distribute emails to their intended recipients. Additionally, they handle tasks such as spam filtering and user authentication.
• Application hosting: Many applications and software services are hosted on servers rather than running on individual devices. These servers provide the necessary computing power and resources to run applications like online games, productivity suites, and collaborative tools.
• File sharing: File servers are dedicated to file storage and sharing within a network. They ensure that files are accessible to authorized users and often incorporate permissions and security features to protect sensitive data.
• Database management: Database servers manage and organize structured data. They are crucial for applications that rely on databases for data storage, retrieval, and processing. Database servers ensure data consistency, reliability, and efficient querying.
• Authentication and authorization: Authentication servers verify the identities of users, ensuring that only authorized individuals or systems can access specific resources. Authorization servers manage permissions and access rights based on user roles and policies.
• Communication services: Servers play a key role in enabling various forms of communication, such as instant messaging, voice-over-IP (VoIP), and videoconferencing. They facilitate real-time interactions and data exchange between users.
• Backup and recovery: Backup servers automate the process of creating copies of data for disaster recovery and data loss prevention. These servers store data redundantly and enable rapid restoration in case of system failures or data corruption.
• Security services: Security servers, including firewalls and intrusion detection systems (IDS), safeguard networks and data from cyberthreats. They monitor network traffic, filter malicious activity, and enforce security policies.

Why are servers important?

Servers are the unsung heroes of the digital age, quietly performing critical tasks that underpin our interconnected world. Their importance cannot be overstated, as they play a central role in shaping how we communicate, access information, conduct business, and store data. In fact, it’s no exaggeration to say that without servers, the internet as we know it could not exist.

Below are some of the key roles of servers, covering functions from data storage to research. 

• Data storage and accessibility: Servers provide a centralized repository for storing vast amounts of data. This data can include everything from personal files and business records to scientific research and entertainment content. Without servers, accessing this information from anywhere in the world would be far more cumbersome and less reliable.
• Global connectivity: Servers enable global connectivity by hosting websites, applications, and online services. When you access a website or use a mobile app, a server somewhere in the world is delivering the content and processing your requests. This seamless access to information and services has revolutionized how we work, shop, learn, and entertain ourselves.
• Collaboration and communication: These computing machines support collaborative work environments and communication platforms. Whether it’s an organization using shared documents in the cloud or friends connecting through social media, servers enable real-time interactions and data exchange.
• Business operations: Servers are the backbone of business operations. They host email services, manage customer databases, process online transactions, and store critical business data. Without servers, modern businesses would struggle to operate efficiently and compete in the digital marketplace.
• Data security and privacy: Servers play a pivotal role in data security. They allow organizations to implement access controls, encryption, and data backups to safeguard sensitive information. This is crucial in an era of increasing cyber threats and data breaches.
• Scalability: Servers are designed to scale both vertically and horizontally to accommodate changing demands. This scalability ensures that websites and services can handle traffic spikes during events like product launches or breaking news. It also allows businesses to grow without significant infrastructure changes.
• Resource consolidation: These platforms allow for the consolidation of resources. Virtualization technologies enable multiple virtual servers to run on a single physical server, optimizing resource utilization and reducing hardware costs.
• Disaster recovery: Servers often include redundancy and backup mechanisms, ensuring that data and services can be quickly restored in case of hardware failures or disasters. This is crucial for minimizing downtime and data loss.
• Research and innovation: Servers are essential for research institutions and laboratories. They provide the computational power needed for simulations, data analysis, and scientific computing, enabling groundbreaking discoveries and advancements.
• Entertainment and streaming: Media servers deliver streaming content, including movies, music, and online gaming. These servers provide uninterrupted entertainment experiences, reaching millions of users simultaneously.

What are the types of servers?

Servers come in various forms, each tailored to specific functions and applications. Understanding the different types of servers is crucial for selecting the right one to meet your specific needs.

Here are the main categories of servers based on their functions, usage, and specialization, from web servers to authentication servers:

Web servers

Web servers are among the most common types and are designed to host websites. They respond to HTTP requests from web browsers, delivering web pages, images, videos, and other web content. Popular web server software includes Apache, Nginx, and Microsoft Internet Information Services (IIS).

File servers

File servers are dedicated to storing and sharing files within a network. They provide centralized file storage and access control, making it easy for users to collaborate and share documents. Examples include Windows File Server and network-attached storage (NAS) devices.

Database servers

Database servers manage databases, ensuring data integrity, security, and efficient querying. They are essential for applications relying on structured data storage. Common database server software includes MySQL, PostgreSQL, and Microsoft SQL Server.

Email servers

Email servers handle the sending, receiving, and storage of email messages. They ensure reliable email communication and often include features like spam filtering and virus scanning. Prominent email server solutions include Microsoft Exchange and Postfix.

Application servers

Application servers provide the runtime environment for running applications and software services. They process application logic and data retrieval. Examples include Java Application Servers (e.g., Tomcat), .NET Application Servers, and Node.js servers.

Proxy servers

Proxy servers act as intermediaries between clients and other servers. They can serve various purposes, such as caching web content, load balancing, and enhancing security. Notable types include reverse proxy servers and content delivery network (CDN) servers.

Print servers

Print servers manage print requests from client computers to networked printers. They queue print jobs, handle printer management, and ensure efficient printing processes. Print server software is often integrated into networked printer devices.

DNS servers

Domain name system (DNS) servers convert human-readable domain names into IP addresses, facilitating internet navigation. They play a fundamental role in internet infrastructure. Popular DNS server software includes BIND and Microsoft DNS.

Game servers

Game servers host multiplayer online games, allowing players to connect, interact, and compete in virtual worlds. They require low latency and high-performance capabilities. Game server software varies by the game title and platform.

FTP servers

File transfer protocol (FTP) servers facilitate the transfer of files between computers over a network. They are commonly used for uploading and downloading files. ProFTPD and FileZilla Server are examples of FTP server software.

Media servers

Media servers store and distribute media content, including videos, music, and live streams. They support content delivery to numerous clients simultaneously. Streaming media servers like Wowza and Adobe Media Server are prevalent in this category.

Authentication servers

Authentication servers validate user identities and provide access control to network resources. They are essential for securing sensitive data and systems. Examples include remote authentication dial-in user service (RADIUS) servers.

Tower servers

Tower servers are a type of server hardware that is designed in a vertical tower form factor. They are characterized by their standalone, upright structure resembling a tower or desktop computer. Tower servers are typically used in small to medium-sized businesses, remote offices, or individual workstations.

Rack servers

Rack servers are designed to be mounted in standard server racks or cabinets. They are commonly used in data centers and enterprise environments where efficient space utilization and scalability are crucial. The best rack servers offer high server density, allowing organizations to maximize the use of rack space and reduce data center footprint.

Blade servers

Blade servers are a type of server hardware designed to fit into a chassis, known as a blade enclosure or blade chassis. They offer a highly dense and modular approach to server deployment. Some of the leading blade servers maximize the efficient use of data center space, making them suitable for large-scale virtualization and cloud computing deployments.

Components of a server

Servers are complex systems composed of various hardware and software components working together to deliver their intended functions reliably. Understanding the key components of a server is crucial for effectively managing and maintaining these critical infrastructure. Let’s explore the essential components that make up a server:

1. Central processing unit (CPU): The CPU is the server’s brain, responsible for executing instructions and performing calculations. Servers often use multi-core processors to handle multiple tasks simultaneously, ensuring efficient performance.
2. Memory: Random access memory (RAM) provides temporary storage for data that the CPU needs to access quickly. Servers typically have large amounts of RAM to accommodate multiple users and applications simultaneously.
3. Storage devices: Servers rely on various storage devices to store data, including hard disk drives (HDDs), solid-state drives (SSDs), and in some cases, network-attached storage (NAS) or storage area networks (SANs) for centralized and scalable storage.
4. Network interface card (NIC): The NIC allows the server to connect to a network, enabling communication with other devices and clients. Servers may have multiple NICs for redundancy and load balancing.
5. Motherboard: The motherboard serves as the main circuit board that connects and integrates various hardware components, including the CPU, RAM, and storage devices.
6. Power supply unit (PSU): The PSU provides the necessary electrical power to operate the server. Redundant power supplies are often used to ensure uninterrupted operation in case of power failures.
7. Cooling system: Servers generate heat during operation, so cooling systems, including fans and heat sinks, are essential to maintain optimal operating temperatures and prevent overheating.
8. RAID controllers: A redundant array of independent disk (RAID) controller manages multiple hard drives to provide redundancy and improved data reliability. RAID configurations can protect against data loss due to drive failures.
9. Operating system (OS): The OS is the software that manages hardware resources and provides services to applications and users. Popular server operating systems include Windows Server, Linux distributions, and Unix variants.
10. Server management software: Server management software allows administrators to monitor and control server resources, configure settings, and perform remote management tasks. Examples include Microsoft System Center and VMware vCenter.
11. Backup and recovery solutions: Backup software and hardware solutions are crucial for data protection. These components help create copies of data and ensure it can be restored in case of hardware failures or data loss.
12. Security measures: Servers require robust security measures, including firewalls, IDS, and antivirus software, to protect against cyberthreats and unauthorized access.
13. Remote access tools: Remote access tools enable administrators to manage servers from a distance. They are essential for troubleshooting, maintenance, and updates without physical access to the server.
14. Monitoring and reporting tools: Monitoring software tracks server performance, resource usage, and potential security or performance issues. These tools provide real-time data and generate reports for proactive management.
15. Expansion slots and ports: Servers often include expansion slots and various ports to connect additional hardware components, such as graphics cards, network cards, and storage controllers.
16. Battery backup: Uninterruptible power supplies (UPS) provide temporary power during electrical outages, allowing servers to shut down gracefully or continue running until backup generators or power sources kick in.

Features of a server

Servers are designed with a set of features that distinguish them from regular computers and make them suitable for their specific roles. These features are essential for ensuring reliability, scalability, and performance in a server environment. Here are the key features that define a server:

• High reliability: Servers are built to run continuously without interruptions. They incorporate redundant hardware components such as power supplies, fans, and storage devices to minimize the risk of hardware failures causing downtime.
• Remote management: Servers often include remote management capabilities, allowing administrators to access and control the server remotely. This feature is crucial for troubleshooting, maintenance, and updates, especially in data center environments.
• Scalability: Servers are designed to accommodate growth. They offer expandable hardware configurations, including additional CPU sockets, RAM slots, and storage bays, ensuring the server can handle increased workloads over time.
• Data redundancy: Many servers implement data redundancy through RAID configurations. This redundancy protects against data loss due to hard drive failures by mirroring or striping data across multiple drives.
• Fault tolerance: Servers can withstand hardware failures gracefully. Features like hot-swappable components and error-correcting memory (ECC) help maintain server uptime in the event of hardware issues.
• High performance: Servers are equipped with powerful CPUs, ample RAM, and fast storage to handle demanding workloads. They are optimized for tasks such as data processing, virtualization, and hosting services that require rapid responses.
• Security measures: Servers incorporate robust security features to protect against unauthorized access and cyberthreats. Firewalls, IDS, and encryption are common security measures in server environments.
• Multiple network interfaces: Servers often have multiple NICs to provide redundancy and load balancing. This ensures uninterrupted network connectivity and optimal performance.
• Load balancing: Load balancing features distribute incoming network traffic across multiple servers to ensure optimal resource utilization and prevent overload on any single server. This improves overall system performance and availability.
• Data backup and recovery: Servers include backup and recovery mechanisms to safeguard data. Scheduled backups and backup software are used to create copies of critical data, which can be restored in case of data loss.
• Resource management: Server operating systems and management software offer resource allocation and management tools. These tools allow administrators to allocate CPU, RAM, and storage resources to specific tasks or virtual machines (VMs).
• Monitoring and alerting: Servers are equipped with monitoring tools that track system performance, resource utilization, and potential issues. Administrators receive alerts and notifications to address problems promptly.
• Virtualization support: Many servers support virtualization technologies, enabling the creation of multiple VMs on a single physical server. Virtualization enhances resource utilization and simplifies server management.
• Energy efficiency: Modern servers are designed to be energy-efficient to reduce operational costs and environmental impact. They often include power management features that adjust resource usage based on demand.
• Compliance and regulation: Servers designed for specific industries, such as healthcare or finance, may include features and certifications to meet regulatory requirements, such as HIPAA or PCI-DSS compliance.

Server software

Server software is a critical component of server functionality and management. It encompasses a range of software applications and systems that enable servers to perform specific tasks, communicate with clients, and efficiently manage hardware resources.

Operating system (OS)

The OS is the foundational software layer that underpins server functionality. It manages hardware resources, facilitates communication between hardware and software components, and provides essential services such as file management, security, and networking. Common server OSs include Windows Server, various Linux distributions, and traditional Unix operating systems.

Server role software

Different types of servers require specific software to fulfill their roles effectively. For instance, web servers use software like Apache, Nginx, or IIS to serve web content. Database servers rely on software such as MySQL, PostgreSQL, or Oracle Database for data management and querying.

Email servers employ solutions like Microsoft Exchange or Postfix for email communication, while application servers run applications and services using platforms like Java Application Servers or .NET Application Servers.

Virtualization software

Virtualization software enables the creation and management of VMs on a physical server. It optimizes resource allocation, offers isolation, and enhances flexibility. Popular virtualization platforms include VMware vSphere, Microsoft Hyper-V, and open-source options like KVM and Xen.

Server management tools

Server management software simplifies the administration of server resources, configurations, and performance monitoring. These tools provide a centralized interface for server administrators, making it easier to manage servers efficiently. Examples of server management software include Microsoft System Center, VMware vCenter, and open-source alternatives like Webmin and Cockpit.

Backup and recovery solutions

Backup software is crucial for creating copies of server data, ensuring data integrity, and facilitating recovery in case of data loss. These solutions often offer features such as automated backups and data encryption. Notable backup and recovery software includes Veeam, Acronis Backup, and open-source options like Bacula.

Security software

Server security software is essential for safeguarding servers from cyberthreats, unauthorized access, and data breaches. It encompasses antivirus software, firewalls, IDS, and encryption tools. Prominent security solutions include Symantec Endpoint Protection, Palo Alto Networks, and open-source options like Snort for intrusion detection.

Content management systems

Content management systems (CMSs), such as WordPress, Joomla, and Drupal, are server-based software platforms that simplify website creation and management. They store and serve web content, allowing for easy content updates and user interaction.

Database Management Systems

Database management systems (DBMS) software manages databases and enables users to store, retrieve, and manipulate data efficiently. Popular DBMS options include MySQL, Microsoft SQL Server, and PostgreSQL.

Monitoring and reporting software

Monitoring software tracks server performance, resource utilization, and potential issues. It generates real-time data and reports, enabling administrators to identify and address problems proactively. Tools like Nagios, Zabbix, and SolarWinds are commonly used for server monitoring.

Development frameworks

Servers often run applications developed using specific programming frameworks. These frameworks provide tools and libraries for building and deploying server-side applications. Examples include Java EE (Enterprise Edition) for Java applications and the .NET Framework for .NET-based applications.

Server guides

Whether you’re an IT professional, server administrator, or someone tasked with setting up and maintaining servers, the guides below can provide valuable insights and assistance. Here, we explore three key areas within server guides: choosing a server, setting it up, and managing it remotely.

Choosing the right server solution

Selecting the right server solution is a critical decision that significantly impacts your organization’s IT infrastructure. These steps will assist you in making an informed choice:

1. Workload analysis: Analyze your organization’s specific workloads and requirements. Determine the type of applications and services the server will host, the expected user load, and performance demands.
2. Scalability: Assess your scalability needs. Consider future growth and whether the server solution can expand to accommodate increased workloads.
3. Hardware considerations: Explore hardware options, including CPU, RAM, storage, and networking. Evaluate the server’s compatibility with your chosen OS and applications.
4. Budget planning: Develop a budget that includes not only the initial server purchase but also ongoing expenses, including maintenance, power consumption, and upgrades.
5. Server types: Compare different server types, such as rack servers, tower servers, and blade servers, to determine which form factor suits your infrastructure and space requirements.
6. Vendor selection: Research server vendors and manufacturers, considering their reputation, support offerings, and warranty terms. Vendor reliability is crucial for long-term server management.

Setting up a server

Once you’ve chosen the right server solution, the next step is setting up and configuring the server correctly. This section provides a checklist for a successful server setup. Note that the guide below refers to an on-premise server setup.

Hardware assembly

Hardware assembly is the initial step in setting up a server. It involves physically installing and connecting the server’s components. Here’s a breakdown of the hardware assembly process:

1. Unboxing and inspection: Carefully unpack the server and inspect all components for damage or missing parts.
2. Rack or enclosure installation: If you’re using a rack-mounted server, securely mount it in a server rack or enclosure, ensuring its level and stability.
3. Component installation: Install the CPU, RAM, HDDs, or SSDs, expansion cards (such as NICs), and other hardware components according to the manufacturer’s guidelines.
4. Cable management: Organize and secure cables to minimize clutter, permit sufficient airflow, and maintain a tidy and accessible server environment.
5. Power and network connections: Connect power cables, Ethernet cables, and any other necessary cables to the server and relevant infrastructure.

Operating system installation

After the hardware assembly is complete, you need to install the server’s OS. Here are the key steps:

1. Boot from installation media: Insert the OS installation media (e.g., DVD, USB drive) and boot the server from it.
2. OS setup: Follow the on-screen prompts to select language, location, keyboard layout, and other regional settings.
3. Partitioning and formatting: Configure disk partitions and file systems to suit your needs. Be sure to set up the root partition and any additional partitions as required.
4. User and network configuration: Create user accounts, set passwords, and configure network settings, including IP addressing and DNS.
5. Software selection: Choose the software packages and components you want to install, which may include web servers, databases, and additional utilities.
6. Security measures: Implement security measures during the OS installation, such as setting up a firewall and enabling security updates.

Network configuration

Proper network configuration is essential to ensure your server can communicate with other devices and the internet. Here’s how to configure the network settings:

• IP address assignment: Decide whether to use static IP addresses or DHCP for network configuration. Assign IP addresses, subnet masks, gateways, and DNS servers as needed.
• Firewall configuration: Set up firewall rules to control incoming and outgoing network traffic, enhancing security.
• Virtual LAN (VLAN) setup: If your organization uses VLANs, configure VLAN memberships and settings to segment network traffic.

Security setup

Implementing essential security measures is crucial to protect your server and data. Key security steps include:

• User authentication: Establish strong authentication methods, including secure passwords and multi-factor authentication (MFA), for user accounts.
• Access controls: Define user permissions and access control lists (ACLs) to restrict unauthorized access to server resources.
• Security software: Install and configure antivirus software, IDS, and other security tools to monitor and protect against threats.
• Security updates: Enable automatic security updates to ensure that the server’s software remains up-to-date and protected against known vulnerabilities.
• Encryption: Implement data encryption for sensitive information, both in transit and at rest.

Storage configuration

Proper storage configuration is essential to ensure data reliability and efficient storage management. Key steps in storage configuration include:

1. RAID configuration: If applicable, set up RAID configurations to enhance data redundancy and fault tolerance.
2. Partitioning: Create partitions on storage devices to organize data and separate the operating system from user data.
3. File system setup: Choose an appropriate file system for your needs (e.g., ext4, NTFS, XFS) and format partitions accordingly.
4. Data backup: Plan and implement data backup strategies, including regular backups and off-site storage solutions.

Remote management

Remote management capabilities are crucial for efficiently administering and maintaining servers. Configure remote management tools and settings, allowing you to perform tasks and troubleshoot server issues from a distance. Popular remote management tools include remote desktop protocol (RDP), secure shell (SSH), and dedicated server management software.

Examples of servers

Servers are versatile computing systems that serve various purposes across different industries and applications. Understanding examples of servers helps illustrate their diverse roles in modern computing environments. Here are some common examples of servers utilized in various industries:

• E-commerce website server: An e-commerce website relies on a dedicated web server to host the online store. This server handles user requests, product catalog management, shopping cart functionality, and secure payment processing.
• Hospital information system server: Hospitals and healthcare facilities use server clusters to store and manage patient records, medical images, and clinical data securely. These servers support Electronic Health Record (EHR) systems, ensuring patient data is accessible to authorized healthcare professionals.
• Financial trading server: Financial institutions employ high-frequency trading servers to execute stock and commodity trades within milliseconds. These servers process vast amounts of market data, make split-second decisions, and execute trades with minimal latency.
• Email hosting server: Email hosting providers maintain email servers that offer email services to businesses and individuals. These servers store email messages, handle sending and receiving emails, and provide features like spam filtering and webmail access.
• Cloud computing servers: Cloud service providers like Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform (GCP) operate massive server farms to deliver cloud computing resources, including VMs, storage, and services like AI and machine learning.
• Online gaming server: Online multiplayer games utilize game servers to host game sessions, manage player interactions, and synchronize game data. These servers enable players worldwide to connect and play games together in real time.
• Video streaming server: Streaming platforms like Netflix, YouTube, and Twitch rely on servers to deliver video content to viewers. Content delivery servers optimize video streaming by selecting the closest server to the user and adjusting video quality based on the available bandwidth.
• DNS server: DNS servers translate human-readable domain names (e.g., www.google.com) into IP addresses that computers use to locate websites and resources on the internet. DNS servers play a fundamental role in internet navigation.
• VoIP server: VoIP servers power services like Skype and Zoom, enabling voice and video calls over the internet. These servers handle call setup, media streaming, and user authentication.
• Online collaboration server: Collaboration platforms such as Microsoft Teams and Slack rely on servers to facilitate real-time messaging, file sharing, and videoconferencing among teams and organizations. These servers ensure seamless communication and collaboration.

Bottom line: The significance of servers in modern computing

Servers are the silent architects of our online experiences, whether we’re perusing our favorite websites, conducting secure financial transactions, or staying connected through email and messaging platforms. 

As we navigate the intricacies of our digital lives, it becomes increasingly apparent that servers are not merely pieces of hardware but rather the enablers of our technological evolution. They exemplify the synergy between hardware and software, offering reliability, scalability, and security to ensure our digital ecosystems function seamlessly.

Given all they are capable of, it’s no surprise how complex servers can be. This guide should provide you with a solid foundation to continue learning about the many different types of servers, and how to establish and run them in your own organization.

Whatever your level of expertise, you can always benefit from a good server management system. Here’s our guide to the best server management software to help you run your network.