A server commonly refers to a computer program that receives and responds to requests made over a network. It receives the request for a web document from the client and sends the requested information to the client computer on the Internet. A device can be both a client and a server at the same time, as an individual system has the ability to provide resources and use them from another system in one go. There are different types of servers, including mail servers, virtual servers, and web servers.

Minicomputers and mainframe computers were some of the first servers. As compared to mainframe computers, minicomputers were much smaller; therefore, they were known as the name of Minicomputers. For instance, a web server may run Microsoft IIS or Apache HTTP Server, which offers users access to the information from web pages or websites over the internet. A mail server is able to run a program like iMail or Exim that provides services of SMTP (Simple Mail Transfer Protocol) for sending and receiving email.

Types of servers

There are many types of servers, which are as follows:

• Webserver
• Application server
• Blade server
• Cloud server
• Database server
• Dedicated server
• Print server
• Proxy server
• File server
• Mail server
• Standalone server
• Domain name service

Web Server

A web server offers web pages or other content to the web browser by loading the information from a disc and transfer files by using a network to the user's web browser. It is used by a computer or collection of computers to provide content to several users over the internet. This exchange was done with the help of HTTP communicating between the browser and the server. There are some examples of web servers given below; you can also download these web servers from given below download links:

• Apache: https://www.apache.org/
• Tomcat: https://tomcat.apache.org/
• Nginx: https://www.nginx.com/
• Savant: http://savant.sourceforge.net/
• Boa: http://www.boa.org/
• FoxServ: http://www.foxserv.net/
• IIS: https://www.iis.net/
• Lighttpd: https://www.lighttpd.net/

Application server

It is an environment where applications are able to run, no matter which types of applications and what operation they perform. It is also known as a type of middleware and can be able to develop and run web-based applications. Generally, it is used to connect database servers and end-user. There are several types of application servers, as well as .NET Framework, Java, and PHP application servers.

Furthermore, it offers users various advantages, such as:

• It allows applications for a more centralized approach to updates and upgrades, which provides data and code integrity.
• It offers security with the help of the authenticating process and centralizing the management of data access.
• For heavy usage applications, it improves performance by limiting network traffic.

Blade server

It is a hardware component, also known as an expansion module, or a high-density server that can be installed into a chassis. It provides advanced functionality, such as allows an expansion card in a computer at a much bigger scale. For example, if more fiber lines are required, additional fiber blades can be added, as a switch or router with the blade server provides complete customization.

Servers can be reduced to a single thin server by removing hard drives, ongoing miniaturization of computing parts, and eliminating internal cooling, which is known as the blade server. Additionally, it can be stored in racks in server rooms as the blade servers are smaller in size and can be replaced more easily. It can save space and make easy a network of hundreds of servers.

Cloud server

It is a virtual server instead of a physical server that runs in a cloud computing environment. It can be accessed by using remote as it is hosted, built, and delivered via cloud computing platform over the internet. It has similar functionality and capabilities to a traditional physical server but accessed through remotely from a cloud service provider. Today's there are different types of server providers, as well as IBM Cloud, Google's Cloud Platform, and Microsoft Azure.

Database server

It is a computer system that allows other systems to access and retrieve data from a database. These servers respond to several requests to the clients and run database applications. Databases can require extraordinary amounts of disk space and can be accessed by multiple clients at any given time. It is also used by many companies for storage purposes. It allows users to access the data with the help of running a query by using a query language specific to the database. For example, SQL is a structured query language, which allows executing a query to access the data. The most common types of database server software include DB2, Oracle, Microsoft SQL, and Informix.

Dedicated server

A dedicated server is a single computer, which is hosted by a company and allows only one company to rent and access. It is dedicated to only one client and cannot be shared with any other clients. Some of the networks require one computer to be isolated for managing connections between all other devices. A dedicated server can be a part of a computer that has the capability to manage printer resources.

Remember that all servers cannot be a dedicated server. In some networks, it can be possible for a computer to work as a server and also able to perform other functionalities. The hosting company offers an add-on service for the client, like administration services to freeing the client from having to worry about the server. The hosting company also utilizes hard security plans for providing safeguard their clients' data.

Furthermore, the hosting company keeps all or most of the maintenance on the dedicated server. Such as:

• It maintains all update activities of the operating system and any installed applications.
• It monitors the server and applications and manages security by intrusion detection and prevention.
• It contains data backups, disaster recovery, and firewall maintenance.

Print server

The printer server manages one or more printers over the network. It is responsible for responding to print requests from several clients, rather than attaching a printer to every workstation. Nowadays, some higher-end and larger printers are available with their own built-in print server that eliminates the requirement for an additional computer-based server.

Proxy server

A computer server that acts as an intermediary between a client and a server known as a proxy server. It is a part of another computer or gateway server that isolates a local network from outside networks. It takes requests from the client and passes it to another server for processing. It receives the requested information from the second server. Then, it replies to the original client as if it is giving a reply own self.

A proxy server loads the page faster and reduces the network bandwidth as it caches all pages that accessed through the network. A page that is not in proxy server cache, it accesses this page via its own IP address. Thereafter, it caches that page and sends it to the user.

File server

It is a computer on a network that is used to store and distribute files. It allows multiple users or clients to share files, which is stored on a server. Furthermore, it can improve performance by maximizing readability and writing speeds.

Mail server

A mail server is a central computer that stores electronic emails for clients over the network. It is much like the post office that obtains emails sent to the user and stores them until it is not requested by a user. It uses standard email protocols to send and receive an email like, simple mail transfer protocol (SMTP) handles outgoing mail requests and sends messages. The POP3 and IMAP protocols are used to process incoming mail and also receive messages. These protocols handle all the connections when users log on to a mail server by using email or webmail interface.

Sometimes, mail servers and web servers are merged in a single machine. However, Hotmail and Gmail (public mail services) and large ISPs (Internet service provides) may use dedicated hardware to send and receive an email. A mail server software must be installed on the computer, which gives permission to the administrator of the system to create and manage email accounts for any domains hosted on the server. For instance, if the domain name 'javatpoint.com' is hosted by the server, it has the ability to provide email accounts ending in 'javatpoint.com.

Standalone server

A standalone server is a serial transmission replacement for the parallel SCSI, and it runs alone. It is an improvement of traditional SCSI and does not belong to a Windows domain. It supports a maximum of 128 synchronous devices at a transmission speed of 3 Gb in a second. It can also communicate with SATA and SCSI and includes two data ports. It offers local authentication and access control for any resource that is generated from a standalone server. Additionally, users only need to create user account other than it does not need any complex actions, as it does not offer network logon services.

Domain name service (DNS)

It is a type of server that is able to manage, maintain, and process internet domain names and their records. In 1983, Jon Postel and Paul Mockapetris designed and implemented the first DNS. Mainly, it was designed to provide websites to end-users over the Internet. It is always required to connect to the internet to obtain services. It includes storage that stores different domain names, internet hosts, DNS records, network names, and other data. It has the ability to convert a domain name into its respective IP address.

How DNS server works?

If you want to visit a website like javatpoint, you have to type "https://www.javatpoint.com" into the search bar of your browser. When the domain name is entered, it can be looked upon as a Domain Name System. Then, DNS translates it into an IP address (like 217.58.217.164). Now, your computer collects the web pages of javatpoint and sends that information or pages to your browser to display on the screen.

How can be connected with other computers to a server?

In a local network, the server connects to a switch or a router that uses all the other computers over the network. When it is connected to the network, other computers have the capability of accessing the server and all its services. For instance, a user can connect to the server to visit a website and can communicate with other users over the internet via a web server.

Although, an internet server acts like a local network server on a bigger scale. Through a web host or an InterNIC, the server is assigned an IP address.

With a domain name registrar, a domain name is registered by which users can connect to a server. Once the users are connected to the domain name (like javatpoint.com), then automatically name is translated to the server's IP address with the help of a DNS resolver.

A domain name is easier to remember as compared to an IP address, which is beneficial for users to connect to the server. Additionally, domain names allow the server operator to change the IP address of the server without affecting the services at the time of accessing the server. Although the IP address can be changed, the domain name always remains the same.

Where are servers stored?

In a corporate environment or a business, a server and other network tools are mainly stored in a glasshouse or closet. These sections try to separate all equipment and sensitive computers from people who have no authority to access them.

Servers that are not hosted on-site and access through remotely are located in a data center. These types of servers allow another company to manage the hardware and enables you to configure remotely.

Can any computer make a server?

Yes. Any computer act as a server with the right software, even a home desktop or laptop computer. For instance, you can install an FTP server program on your computer that allows you to share files between other computers over your network. However, you can make your home computer a server; you have to keep some important point in your mind:

• Your computer and the related server software must be in a running mode that to be accessible at any time.
• When your computer is in server mode, and other users are using it. Then, its resources (like bandwidth and processing) will not allow doing other things.
• To connect a computer with a network, and the internet connection can generate many problems for your computer.
• If the services become popular, which you are providing, a typical computer can not capable of handling all of the requests.

Are servers always on?

Yes, most of the servers are always on; they never turned off. Because the servers offer services that are continuously needed, accordingly, if servers fail, they can generate many problems for the network users and company. That's why servers are usually set up to be fault-tolerant (capable of operating satisfactorily at the presence of one or more system failure conditions.) to reduce these types of issues.