20 to 30 years ago, when you needed to find any information - you used to go to a library of books where you got the information on almost any topic. But today we are doing, just sitting in front of a computer or a smartphone and connecting to search that information. This library is much more powerful than any other library in the world. You can access any information at any time from anywhere and this is the World Wide Web. Today we are so much dependent on the web that we can not live without the web. Anyway, it's just 20 years ago when the web was invented. Nevertheless, within a very short period of time, it gets much popularity and becomes a part of our daily lives. So let's start to search the known and hidden information behind the World Wide Web.
is there any difference between web and net ?
Many of us think that the web and the internet are the same things. And as long as you are not clear about this phenomenon, it will not be possible to proceed to the post. So let's clear the matter.
The Internet - A vast network of worldwide computers. It can process a lot of work (called application) and "Web" is one of them. When you send an email to someone, you are using the internet - because you need a connection to send your message through which it can reach another computer. Again, when you are chatting with someone, you are still using the Internet - as your message is repeatedly sent and received through the network. But when you update your blog or search for info on Google, you are accually using WEB on the Internet. For more information about the Internet, read my article "How Does the Internet Work?".
The World Wide Web is a comprehensive collection of text pages, digital photographs, music files, videos, and animations across the world, which you can access through the Internet. The most important thing about the World Wide Web is that each of its information is connected to each other. The most basic tool of the WEB is to create text pages (eg: this page), also known as a webpage. The collections of those pages on a computer are called websites. Each webpage (including this page) has highlighted phrases that are called links (or hypertext links). By clicking on any hypertext link you can access another page and thus the process going on.
How does the computer speak the same language with each other?
The most important thing on the Internet is that every computer on the Internet can exchange information with each other. And this is the most interesting thing on the Internet. It was a rare incident to see, the computers, had the ability to exchange information among the back of the counter in the 1960s, 1970s, 1980s. Each machine was manufactured by a different company and no one was able to understand the language of each other. Personal computers in the 1970s did not even have the competency to run a common program. Each computer could run only those programs which were exceptionally written for them. Things like email and chat were then impossible.
But in the year 1980, a large computer company, IBM, earned a great reputation for their new invention on personal computerization. Soon most people cloned their computers and started working in the same way. After that, the great invention of Microsoft developed its software called Windows. It was possible to run all the computers in the same program after installing Windows in every IBM computer. Still, it was not so easy to connect and talk computers to each other. For example, a large computer and science research computer could not establish relationships with individual computers. So how could the computers of these different languages be able to talk to each other?
This great problem is solved by an English computer scientist named Tim Berners-Lee. He worked in a European laboratory in the 1980s, where people from different universities worked with the computer in different languages. As a result, it was not possible to share significant information among the people because their computers were not able to exchange information with each other. And then Tim Berners-Lee surprisingly discovered a thing that made the computers possible to talk to each other.
What is the difference between HTTP and HTML?
However, the previous computers were very incompatible and they used to preserve the data using the ASCII (American Standard Code for Information Interchange) method also known as "plain text".In ASCII 0-255 numbers work as a variation of various letters, numbers, and keyboard characters (such as A, B, C, 1, 2, 3,%, &, and @). Team Burners-Lee uses two basic systems of ASCII, in the computer terminology that are called protocols. Then all the computers in his lab started following these two rules and soon he realized that the computers were able to exchange information easily among them.
He named the first rule as HTTP (HyperText Transfer Protocol). This is an important method by which two computers can exchange any information by talking to each other. A computer (called a client, and a program that uses the Web browser) is asking for any information from another computer (called a server or web server) as a normal message. After that, the client and the server chat with each other for a few seconds where the client requests the information from the server and send it to the client(browser) if the server finds it. This HTTP conversation between a web browser and a web server is a lot like "consumer and the shopkeeper". When a client asks the shopkeeper if the product is available, the seller may answer"Yes. You can take it!". It works the same way, it is a language that every computer knows, and in this way, the computers share files with each other.
It is important to recognize the file to execute that come via HTTP. So here Tim Berners-Lee showed his another talent. He uses a common language to share information that is known as HTML. Every computer can understand HTML as it relies on ASCII systems. HTML contains some special codes that are known as tags. Web browsers can read these tags and shows bold fonts, Italic, Headlines, tables, and images accordingly. If you want to see the secret HTML code of any webpages click on the View page source option from the browser and you will see the magic.
World Wide Web depends on HTTP and HTML systems. HTTP is a common way through which browser computers request webpage to the server computer and HTML is the webpage that all computers can read and display.
When the web browser connects to the server
Web browsers (clients) and servers exchange information by using HTTP language, not the English language or another one. What are the hidden conversation has been gone when you load this page. See Below:
»The web browser asked
GET /world-wide-web-explained HTTP/1.1
Host: zhost.eu.org,
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:47.0) Gecko/20100101 Firefox/47.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8,
Accept-Language: en-gb,en;q=0.5,
Accept-Encoding: gzip,deflate,
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7,
Keep-Alive: 300,
Connection: keep-alive,
»Response From The Server
HTTP/1.1 200 OK
Date: Sat, 02 Feb 2019 04:38:02 GMT
Server: nginx
Content-Encoding: gzip
Content-Type text/html; charset=UTF-8
Location http://zhost.eu.org?post=6&name=world-wide-web
Want to know the meaning of these messages? Here the browser describes Firefox as the name of the software. I'm running Windows 10 operating system. Moreover, the browser is stating what type of files it supports and which language it supports. It also means that any compressed files will support it (such as gzip). And meant (/?post=6&name=world-wide-web) This page requires the browser. In response to the browser, the server says that he uses nginx software and it is sending a compressed File (gzip). Moreover, the server also says that it is sending text / HTML files made by UTF-8.
At the beginning of the server reply, we can see an "HTTP / 1.1 200 OK" message has sent. "200" is the status code -that interprets the server finds the file that is being requested and has been sent. The server can also provide more code. For example - if no webpage or file is found, the server will send the code 404 "Not Found". Again, if a webpage is moved from one link to another(Permanently moved)- 301 code will send. If the server is down to fix (Service Unavailable)-503 code will send and the browser then understands and try to load again.
I hope there is no difficulty in understanding the HTML and HTTP topics. If you have any questions, then you can tell it in the comments.