We've already talked about servers , but in a generic way, without being specific about the type of server, since they exist with the most different purposes and uses. It is difficult to say which is more important, but it is certain that much of what we know today would not exist if one of these types did not exist – the web server. Do you know how to answer what a web server is?
The History of the Web Server
Telling a little of the history of the Internet helps to understand what it is and the importance of web servers.
To begin with, we must define what the web is, which so many people talk about, but few know how to explain what it is. In English, the term web has the sense of a web, such as a spider's web, which is made up of many threads that are connected together at certain points.
The Internet is a network that has a similar configuration, that is, several smaller networks interconnected with each other at certain points, in an arrangement that resembles a spider's web.
But it was only at the end of the 1980s that the term began to gain prominence, thanks to Sir Tim Berners-Lee who created the first browser whose objective was to display pages in hypertext for the exchange of information in the university and scientific environment and which received the name of World Wide Web or worldwide network in free translation, since it proposed to interconnect research and academic networks on a global basis.
At the same time, he also created the first web server, here in the form of a service / software, that is, it was the service that would be able to display the content of hypertext pages, and which was called CERN httpd . Tim Berners-Lee's two creations served as a pattern and development base for everything we know and that came later.
Saying that web servers were born along with the Internet or that the Internet was due to them, although it is not entirely true, is partly true, because the Internet today is based on web servers and on this work initially developed by Berners- Lee.
Thus, the WWW that we use in front of each domain that we type in the browser, indicates what type of content we are accessing, that is, a content similar to that in the late 80s was created to be displayed in the World Wide Web browser.
Therefore, world wide web, as well as web server, can assume different meanings, being first a browser name, the type of content associated with a domain that is accessed in the browsers that exist today and, more generally, the Internet itself , if we think of the network that is made up of several smaller networks.
Web server - the hardware or equipment
In order for all of this that we have discussed so far to be possible, another point is fundamental – the hardware or the physical web server.
Whether the browser, whether the content that the browser gives access to and displays to users, whether the services and even the interconnected networks that make up the Internet, all of this can only be used because there is hardware that stores all the systems and services associates. This is when we talk about a web server as a machine or hardware.
As equipment or hardware, a web server is very similar to home computers, more precisely the desktops or those we had before laptops dominated the market. At first, the components have the same roles, that is, processing, memory , storage and network communication, but the amount of information that servers can handle and store is much greater than personal computers.
A typical web server may have several pairs of multi-core processors, a few hundred Gb of RAM and several Tb of storage, all of this to be able to support thousands of connected users sending and receiving the results of requests, such as a page from a website or an email message .
Therefore, the role of a server, just like your personal computer, is to have installed systems and services that perform certain tasks, delivering expected results to users who connect to it. Or, almost redundantly, he serves services to people.
Web server – the software or system
When you access anything on the Internet, you use protocols, which are nothing more than very precise and strict sets of rules on how things should be done. Thus, there is a protocol for web pages (http), a protocol for transferring files with the server ( ftp ), a protocol for receiving e-mail ( pop3 ), among many others that were created according to the service you want to use.
That's because unlike your computer, where you open a program (service) when you want to do something specific, on the server the way you communicate with it, that is, the protocol you use, which will determine which software - or service case – the server will run to interact with you and respond to you.
In fact, unlike what happens on our personal computers, where programs are opened according to need, a server has all its services running all the time and it is "listening" to the ports through which user requests for each service.
When you open your browser (Firefox, Chrome, Internet Explorer, etc) and type https://www.olx.com, the server (machine) on which the OLX website is hosted , identifies that the communication is taking place through the HTTP protocol and therefore it is a web page and thus delivers the content request to the Apache web server (service), which is the service we use to display web pages.
The same situation above happens for each of the services that a web server provides, such as e-mail, in which depending on the protocol being used by the person making the access, the corresponding service on the server is accessed and it can be POP3 , IMAP or SMTP .
If at the beginning of everything, the content and the protocol designated hypertext pages, today a web server can supply users with various services, such as database, ftp, multimedia content, various applications and the already mentioned e-mail and pages, each service being analogous to each piece of software you have installed on your computer.
The most popular on the market
When it comes to a web server, just as we have different programs for managing e-mail or music players on our personal computer, there are different services for managing web pages within a server and acting as a web server!
Undoubtedly the most used on the market today is Apache and almost half of all web servers currently available use this software to serve web pages. Although it has its own license, it is open source software . Apache has a modular architecture and so you can install modules that add functionality, such as mod_security. Which, as you can imagine, increases the security of the environment.
Another popular web server is NGINX, which was born with the aim of being able to serve a large volume of users and requests coming from these users, also having the role of demand or load balancing and can even act as a proxy. It accounts for nearly a quarter of commercial web servers.
Apache Tomcat or simply Tomcat, as it is more commonly called, although it serves other purposes, is primarily used to serve pages based on the Java language, as an alternative to PHP and ASP.net and which dominated the scenario of creating and hosting websites and for this reason it has played a fundamental role as a development alternative.
And how to talk about ASP and ASP.net language and not talk about IIS (Internet Information Services), created by Microsoft to support sites in these programming languages. As well as PHP and which works under the Windows Server operating system . Usage data is slightly different according to different sources and despite falling in recent years. It is estimated that close to one in four web servers in the world use IIS.
There are other web servers, intended for more specific and restricted situations and therefore have a very low level of adoption in the market, always less than 1% and therefore, just to name the best known. We have Node.Js, Litespeed and GWS, the latter being created by Google to serve its own infrastructure.